I know I'll never get around to it, but I wanted to design four subclasses.
-------------- Rogue - Thief:
Gains bonuses to Rogue skills (Mechanics, Sleight of Hand, Stealth) on start and at PL intervals.
Disadvantage: Lower Fortitude or Will; receives a small incoming damage increase (5 percent?).
Because of Sleight of Hand (needless skill), it's tough to evenly assign abilities that would suit a Rogue. This would help bridge the gap. The biggest bonuses would come at PLs 7 and 9 to encourage single classing it. The disadvantages would be minor and easy for the player to manage.
---------------- Rogue - Bounty Hunter:
Gains PL bonuses to Explosives and Mechanics (+3 each seems fair since they're both lousy by default) on start and learns free abilities at PLs. These abilities would focus on ensnaring enemies, disruption, and traps.
Stuff like: Lasso: A ranged pull effect; same as Lurkers' vine snare. Bolas: Ranged knockdown that deals Crush damage with an Immobilized follow-up. Fragmentation Grenade: AoE that deals best of Slash/Crush damage, has same effect as Expose Vulnerabilities. (-2 AR, -10 Deflection) Hallucination Grenade: Aoe that inflicts Confusion, Flanked, and Shaken for a modest duration; deals small amount of Raw damage. Black Powder Mine: Seal ability that deals Burn damage, Hobbles and Blinds enemies. Affliction duration and damage are low but the effect pulses. Pitfall Trap: Seal ability that triggers a pulsing knockdown effect similar to Slicken but with added Piercing damage (and a shorter duration and AoE).
It would be interesting if the traps and bombs could have additional scaling from Explosives and Mechanics but I'm not sure if this is possible.
Disadvantage: Lose access to all Rogue Invisibility abilities; -15% Stride. The Bounty Hunter is always equipped with noisy, cumbersome gadgets and doo-dads.
Lay down a trap and a Seal during Stealth, then pull a vulnerable enemy into the stacks; or use group ambush tactics to set up battlefield control.
--------------- Wizard - Arcanist:
Gains +1 Wizard spell cast per PL. At PLs 7, 8, and 9, respectively gain an additional spell cast for Wizard spell levels 1, 2, and 3. +2 Arcana
Disadvantages: Cannot use Grimoires.
Pretend Rekvu's gear and Blood Mages don't exist. This is basically the D&D Sorcerer brought to Deadfire: an arcane caster naturally attuned to magic that lacks formal training: a hedge wizard. The PL bonuses would work as auto-passives per PL, so the extra casts would be granted after reaching a new PL (meaning it would get two casts at PL9 single classed, PL7 multi). Sadly, you wouldn't get to use unique spells from Grimoires so the Arcana boost is there to add scrolls into the mix.
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Barbarian - Outlier:
Shout abilities gain effects used to destroy the essence of magic.
Gains "Magebane Strike" at PL2. Upgrades to "Magebane Collapse" or "Magebane Ambush" at PL 5.
Disadvantages: Loses access to Carnage and abilities that inflict or modify Carnage (Barbaric Blow, Accurate Carnage). Frenzy loses Fit inspiration. Cannot use scrolls.
All shouts gain a brief (4s base, scales with PL) beneficial suspension effect ala Arcane Dampener. The base duration is low, but I thought it ok since shouts are cheap to cast. PL 5 Shout upgrades gain a lesser Concussive Tranquilizer effect (-20 seconds to beneficial duration); PL9 upgrades enhance this to -30 seconds and apply an additional interrupt after three seconds. Magebane Strike: Full melee attack, Interrupt on Hit, Veil Piercing, +25% damage, +10 Accuracy. Costs 2 Rage. Replaces Barbaric Blow.
Upgrades to Magebane Collapse: Full melee attack, now interrupts on Graze and removes enemy Concentration. +1 PEN. Replaces Crushing Blow.
Or Magebane Ambush: Full attack (melee or ranged), lowers duration of (flanked) enemy beneficial effects by 30. +1 PEN. Replaces Barbaric Smash.
The idea was a revamp of the Mage Slayer, which was a meme on launch and remains to this day (Eric Galad's awesome mod makes it better). Instead of strictly slaying mages, the Outlier goes after the essence of magic itself and works as a tear down class: something reserved for Wizards and Rangers in Deadfire.
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Other than those, some odds and ends like merging Arcane Archer with Ghost Heart (Checoden's mod did the same with Sharpshooter) or smaller difficulty tweaks that are easy to implement.