First of all: I love the Idea of a full rework on skills!
however there are a few things I dont like about this "classless". Classes are an important thing to identify yourself with. You dont want to play with 4 humans in a team all looking the same and aiming for the highes dps build... It's all about DIVERSITY!
so lets start to evaluate:
What is the challenge?
Killing without getting killed. A progressive play style to get XP and Item rewards for further challenge.
What we got to rule this?
495 attribute points, 131 skill points, 30 skills per class, 15 weapon types and a shield, 12 Item slots, 4 main attributes, 5 damage types, 2 ways to apply (basic attack/spell) a charge system and health regeneration. (this is btw the reason for classes to appear similar...)
So how to get diversity in here?
Lets talk about classes and roles:
- The class is something to preset your starting point in the game with certain class unique powers you can specialize in. (in vanilla it's 5-15 points per attribute, different skills and chargebar boni...)
How to be unique with this low kit?
By combining the chargebar mechanic with the skills. The engineer is a good example, the outlander is a bad one, his skills only benefit passively from the buff. I'd like to see the outlander automatically summon Shadowling Brute when fully charged (1 min last and 3 min cooldown). though i like the 3 skill trees idea to open up some specialisation per class.
- The role is something to preset your main focus on game mechanics with certain role unique powers you can optimize. (the attributes promote "critter" - "caster" - "tank")
How to implement roles into the game?
Leave the 4 stats system and open it up for any viable affix you want to invest in.
Roles should be available for all classes even if the class preset puts them into a certain area.
They could be Item or weapon related so further progress and optimization also means to leave things behind. (Item specialization could be realized by spending attribute points on the preferred weapon type to optimize handling and damage output. (compare scrolls passive boni) )
Back to the Skill issue... There are some models to go through. I'd prefer a mix of class unique skills and "open" skills which could be passives everyone can benefit from.
Unlocking Skills will stay slaying monster/exp based. its just a question about the path we choose
Player level based (vanilla) using graphs as the main requirement to enable skills and it's 15 level.
Stat point based - IMO to be worth implementing there shouldn't be a skill limit. In case of your "only 4 skills" Idea, if you link them to stat point investment that would mean I've unlocked my 4 skills at ca. lvl 10 and then running around spending statpoints here and there with no reward then the affixes OR I have to wait for level 20 to finally unlock my second skill...
Tree based - easy implemented through Player Editor there you can set a required Skill for each Skill the player "knows". this opens up different paths to go deeper. lets say each level i can choose between 2 skills, most of them have to be passives to gain a slight bonus into 1 or another direction (by adding a stat and having a passive skill using a stat counter for the effect level/stat percent to currently use)
Something in between: Lets say you have a starting skill surrounded by others and its based on where you spend your attribute points to to unlock another skill. These can be single instance castable skills or "modifier" skills to edit the damagetype, range, cooldown etc. So we come up with a serious Skill map mainly with passive increments to active skills or atributes controlled by the way you invest these Attribute points. My suggestion on this would be to rework the existing 4.
To keep this open to other mods I suggest creating a new attribute system that conveys the "old" stats into the new ones so every existing class can be implemented (lets say 35%str+60%Foc=X% of a new Attribute. New attributes could include the 5 damage types or other boni like melee/range, 1h/2h weapons etc.)
...and there is health regeneration! Tho GOD under the effects. Sure you can stack your resistances but they won't heal you

*btw isnt that blasphemy creating an "anti-synergies" mod?
