Kaylon

Just +1PL (over Hot Razors Skewers/Shark Soup) isn't a big deal and you lose much more.

Full melee is perfectly viable - front Eder (fighter/rogue) + Pallegina (paladin chanter), behind them Aloth (fighter/wizard) with Citzal Spirit Lance and PC with WotEP (soulblade/trickster, fighter/barbarian, etc.), back Xoti (monk) with Instruments of Pain (until she gets WotW). You can also replace Pallegina with the PC and use instead Serafen (cipher/barb) behind.

Berserker/fighter, berserker/steel garrote, berserker/skald can be built to be self sustained at any level and don't need special healing at all. Then it's even worse than I thought, because the point of going berserker is to stay afflicted the entire fight in order to benefit from the bonuses of the set and the FF goes against that. Also I don't even see the point of mentioning confusion in the heal/wounds discussion because Frenzy isn't something you can spam for free and use as a source of wounds and heals.

To counter the self damage and be at least self sustainable you have to move around all the time and heal. If you need other characters to work for you instead of doing damage it's not very efficient. PS. You're not confused by the boots, you're hobbled.

That happens only if you move constantly your character which becomes boring very fast (without mentioning you can trigger disengagement attacks...).

Since many bonuses require to be afflicted, the berserker becomes the ideal candidate (his speed bonuses help also with the high recovery of the plate). Overall the ice set seems also to be made for a tank and you should pick another class that has some kind of health regeneration to make the self DOT manageable. I think a paladin steel garrote fits the best this role and Spirit Frenzy/Barbaric Shout can keep enemies afflicted and allow you to also drain health from them. You can also use Grave Calling as backup weapon. Another possibility would be a street fighter with min resolve and max intellect - use a blunderbuss to afflict himself with a long lasting Powder Burns, then switch to weapon and shield. As a second class you have more freedom here - a black jacket who can switch easily between weapon sets fits well and his Armored Grace reduces greatly the armor recovery. PS. Also a pale elf fits perfectly here because his racial bonus covers the elemental weakness of the plate.

It's not strange, it's the best approach.

Those procs require party members, not allies. Ranger's companion is considered a party member and indeed you can exploit his death because he doesn't get injuries. From what I remember you can get at most +4 MIG/RES until the end of combat.

Obviously you can't tank them with a rogue. However I remember there was a video of a monk who soloed the encounter mostly using shoot and run tactics, it should help you. The right resting bonuses, food, scrolls are required to succeed. The bog is pretty big and you have plenty of space to run around. The dragons have only AoE spells which are easy to dodge with high running speed, however single target spells from casters are harder to avoid (especially Llengrath) and you have to make sure to kill them first (with a little help from the dragons).

IMO barbarian works much better as a MC. Berserker/devoted is a very powerful melee combo who can use Clear Out as a cone version of HoF and has some very good weapon choices (Lord Darryn's Voulge, Amra, Karaboru). Berserker/troubadour is also very powerful if you decide to use Grave Calling and spam Chill Fog by killing your own skeletons (however it's not really a melee build). Another great combo is rogue/barbarian - with a 2h weapon he can easily spam Barbaric Smash and also trigger Blood Thirst (if you have a priest who can cast BDD, then a berserker/streetfighter with Voidwheel is devastating).

Then you have a bug.

Dragon's Dowry works with the Ring of Focused Flame.

I suppose you can get him as soon as you leave Port Maje. You just need a rogue and/or a paladin lvl5 who can apply Gauging Strike and/or Brand Enemy on the dragon. (an assassin with high perception, using an arquebus with modal activated has the best chance to apply Gouging Strike).

Besides might you have also Harley pet, High Harbinger's Robes, Sash of Judgment, Ajamuut's Stalking Cloak (if you stay invisible), Infamous Captain ability and probably a few consumables. And PL increase should affect at least Gouging Strike.

Paladin/Soulblade is another option - great defense, accuracy and damage.

You don't want to go into melee when you do stealth kills. After becoming invisible you have just a few seconds before the combat ends and then you become visible again. And if that happens near the enemies then you become a sitting duck and get clobbered to death. Shadowing Beyond is too expensive and I think it breaks if you're using dots. You should use just Smoke Veil.

If it requires 3 other classes I wouldn't call that easy, and those debuffs aren't granted or free either... I didn't say it's not possible to play a dot druid in potd, I just said it's less effective than other options.

If you don't plan to play on potd then druid's dots are of course viable. However in potd enemies have also high HP, high corrode AR and also high fortitude. Fortitude is the highest defense in the game and is not that easy to debuff, especially in an AoE. Add to that the limited number of spells of the druid and you easily understand why the effectiveness of his dots can be crippled. I don't even mention that dots will clash with other spells of the same level you want to use. A streetfighter/ascendant using mortars with just Disintegrate+Gouging Strike+Deep Wounds (and you can add depending on the situations Recall Agony, Soul Ignition, Arterial Strike, Toxic Strike, Pernicious Cloud) has speed+accuracy and can keep the dots going the entire fight.

For pure caster I would go ascendant/helwalker. Essence Interrupter with modal can replenish focus very fast and you can spam high level spells without running out of mana. Later you can use the Chromoprysmathic Staff with Instruments of Pain to generate focus even faster.

The druid has many dots, but there are many enemies immune to disease/poison in the game.... A rogue (streetfighter can easily work here with Powder Burns debuff) using mortars can apply many dots in an AoE. Add an ascendant who can also spam dots and you have a great combo. If the streetfighter feels too squishy you can use a trickster instead.

Yes, FoD itself is bad. However its upgrade, Eternal Devotion is very good. Basically you should start the fight with a big alpha strike (like from an arquebus) to make FoD count and after that you just refresh the buff when needed. With Retribution, Eternal Devotion and Brand Enemy the paladin does respectable single target damage.

Clearly Darcozzi paladin (Fires of Darozzi Palace is really free damage earlier and Inspiring Liberation is a great long accuracy buff for himself or others) - by far the best tank in the game and once he gets Sacred Immolation he becomes also a great damage dealer. If you want a more offensive one from the start (and not too squishy either), then you can try a monk. The fighter is a solid class but with nothing exceptional, while the barbarian is great (later) vs multiple enemies swarming you, but ineffective vs scattered ranged enemies or bosses. The rogue deals great melee damage but is very squishy. The chanter is not really a melee fighter - he usually deals damage with his chants and ranged weapons from behind his summons.

Ranger/rogue with the Red Hand is the most efficient build indeed. Geomancer can be fun sometimes if you like micro, but it's less effective against high level enemies.

The focus you generate is proportional to your weapon damage (ie your damage bonuses) and the SA bonus depends on your focus to which are applied again all the damage bonuses. (It works a bit like wounding in PoE1 which was affected twice by might.)

To add to what Boeroer already explained very well: the rogue can also generate free focus from misses through Riposte/Outward Spikes (from shield) or through disengagement attacks (from Ryngrim's Repulsive Visage) the SA bonus is affected twice by the weapon bonuses (when is generated and also when is applied), thus a rogue can generate the highest dps with SA another alternative to Tuotilo's Palm is Magran's Blessing which can also generate free focus through its damage shield (which is considered a shield attack and benefits from the Burning Strike enchantment and other damage bonuses including sneak attack/deathblows); the dmg shield targets reflex which can be lowered using flail's modal. Of course the monk can also generate free focus through Swift Flurry/Heartbeat Drumming (Sun and Moon is very good for that) and even some disengagement attacks (with Left Hand of the Obscured equipped), however his SA damage is lower overall. A good ring to use is the Ring of Focused Flame which affects the first head of the flail (to avoid misses from SA) and also the damage shield.