Ok you dont really NEED the wiki to play but in these types of games very few people dont spend some time looking at their character´s stats and numbers and fiddling around with them.
The thing is, the game doesnt tell you what many of these mean (in either the Inventory Screen or the Character Screen) or do and even less about what is affecting them. Some are only mentioned in character creation. The game doesnt let you understand the system you are playing with. So we gotta consult the wiki, and even then you have to do some trial and error (activating->checking screen->deactivating->checking screen) before finding out if that 145 Deflection is the the base deflection or because I got Defender on BB Fighter or if that 216 Stamina is because I have high CON, I am a Barbarian or because I got the +20 Stam boots on.
I cant see the calculations and I dont know what they mean. Unless I consult the wiki, which doesnt solve the numbers bit.
The game does provide some calculations for stats like Might and Athletics but despite the ample tooltip size there isnt an explanation for what they do outside the character and level up screen:
And the base value doesnt display the same calculation as in char gen (though thats understandable as chargen stats are meant to be your "base", but it would still be nice to see where that base is coming from outside char gen).
Speaking of Chatacter Creation, the only defenses mentioned per class are Deflection (which it doesnt explain, though that is understandable as it can be interpreted as overall defense [which it isnt] and you dont want to overwhelm the player with too much information):
And AFAIK there Concentration/Interruption mechanic isnt mentioned outside Resolve and Perception (which, once again, arent expanded upon beyond char gen).
The Inventory screen does have tooltips that work when you mouse over certain things. It would be nice to have these (with more detail like calculations and descriptions obviously) for the stats like Stamina. Or at least allow us to right click on the stats to see a detailed popup like with Might and Athletics in the Character screen.
And then theres the thing with diferent damage types (shock, burn, freeze, corrode, raw, piercing, crushing, and slashing) for which natural resistances or the ones that your gear give you are unkown (chainmail good versus slashing, bad versus crushing but these defenses and damage types arent displayed anywhere in the Character Screen). DT is a mistery beyond "the more the better".
So new players or players simply trying to understand how the numbers work are gonna be like:
Do I want more Fortitude or more Reflex? Does it matter? Does 17 Def applies to Burn damage or does it depend on what the ability is? Does Defense matter at all besides auto-attacks? Do I have to exit the game to consult the wiki every time?
What Im saying here is basically: We need more information feedback on our character´s numbers. We already got a mouse-over calculation text on the combat log, why not add that into a popup-tooltip like the character Screen one if you feel its too crowded for calculations?
I feel there are many ways already within the game to make the player understand the whole system better without having to alt-tab to the wiki every time he gets a new pair of boots.
This is a good start:
I just think it needs to be fleshed out more.
TL; DR: More detaled Tooltips to prevent wiki-alt-tab-diving and better understanding of the new game system from the player, plus better character number-management/building.