This is such an overwhelming change that it's really more of a suggestion for D:OS 3 than something likely to be implemented in D:OS 2.
That said the system looks pretty interesting. But you really have to remember to use the appropriate terminology used by D:OS. For user-activated things, use "Skills" not "Abilities". Makes it a bit easier to understand if it's consistent.
Wisdom (replaces Memory) - a point in Wisdom opens up one Skill Slot for abilities and allows for items of one level higher to be identified.
I guess this means that instead of there being 5 levels of Loremaster which magic items can fall into, identifying items will be based on the item level. It also looks like all items level 5 and below are auto-identified by default since everyone starts with 5 Wisdom.
Unfortunately, the item-identification part still wasn't thought out very well at all. Players can reach about level 30, but it's highly unlikely that anyone is going to pump more than half that amount of points into Wisdom, just because it's not great to have a lot of memory, but all your attacks are really weak because you haven't put any points into attributes which increase your damage.
That means that about halfway through the game - probably much earlier - you'll no longer be able to identify items yourself and have to have merchants do it.
Wits - a point in Wits grants bonus Critical Chance and improves the value of items that can be found or stolen.
Wits becomes the stat of thieves and rogues that absorbs some benefits of Lucky Charm and Theft into itself as part of changes to the skills.
bonus Critical Chance, or bonus critical
damage? Just wondering since backstabs are a guaranteed crit, so bonus chance won't do anything.
To start with, gone is the distinction between combat and civil abilities, as it takes away from the ability to have a non-combatant on the team, or otherwise to vary the balance between combat and out-of combat utility of party members.
This is an immediate problem flag.
There is no room for a non-combatant on the team. This is more of a talky, quest-solving RPG than a mindless monster-slayer, but there still is a lot of combat.
Splitting of abilities between combat and civil was definitely a good change because it meant not having to fall behind in combat abilities by increasing non-combat abilities.
Marksmanship: Increased bow/crossbow range. Unlocks abilities based on using a bow or a crossbow.
This is very questionable. What do you imagine the base range of bow/crossbow weapons to be? What do you imagine the maximum range would be with this ability maxed out? The usefulness of increasing the range will depend a lot on how far enemies can appear in encounters.
There's not much point in having a +10 to range (total range of 25) if all enemies are within 15 meters. There's also not much point in putting enemies 25 meters away who have to spend two turns moving to get within range of the players. But if they start out from that 25 meter range and CAN hit players, then that forces one member of the party to be a ranger and to spend all their ability points into Marksmanship. This gets worse if you cut the default range on weapons to 5-10 meters, in which case melee enemies can walk straight up and attack. (And it still forces Rangers to spend all their points onto Marksmanship.)
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You seem to have neglected any ability which increases elemental damage WITHOUT creating a surface. So either you're cutting out a lot of magic skills, or you're having more spells create surfaces than before, which leads to out-of-control surface spam.
Skills can only be learned not by simply having a point in a single ability, but rather by having an appropriate number of points across abilities that are relevant to the skill effects.
Okay, this might be another problem. Not only do you only have 3 points plus only 1 per level, but now you need multiple points into multiple abilities to be able to use skills?
It would be hard enough in the first place to fairly balance all the skills in the game so there's a relatively even distribution between all the abilities. Look at some of the categories you have: "Martial - Unlocks skills based on using a melee weapon". - That covers a LOT of skills. "Assassination - Unlocks skills that require or enable invisibility." - I can probably count the abilities that affects on one hand.
Adding in dual-ability requirements will mean that users will have even fewer skills available, and it gets worse with ones which require multiple points, forcing them to spread themselves over a ton of ability categories just to get a basic library... and doing that means the power of the ability's passive benefits is weak.
It would be difficult to balance.
