I never even brought up Abilities. Just talked about Skills.
There are 3 Ability Trees in the Ability wheel: Magic, Ranged, Melee.
Each Tree has 2 sub trees. Those sub trees are broken down into 6 other sections.
Each Tree has a total of 168 total abilities that you can learn (broken down into 56 per sub tree). So, that's 168 total possibilities per main tree for a grand total of 504 tree specific abilities. Then there are 3 "misc" trees (don't require a specific weapon) with 7 abilities each for a total of 21. TOTAL 525 Abilities you can learn.
Numbers mean very little, It's just to show that you can easily swap between any weapon and any skill set you want. 36 total combinations of weapon abilities (not include the misc).
Code:
Fist + Hammer
Fist + Blade
Fist + Shotgun
Fist + AR
Fist + Pistol
Fist + Chaos
Fist + Blood
Fist + Elemental
Hammer + Blade
Hammer + Shotgun
Hammer + AR
Hammer + Pistol
Hammer + Chaos
Hammer + Blood
Hammer + Elemental
Blade + Shotgun
Blade + AR
Blade + Pistol
Blade + Chaos
Blade + Blood
Blade + Elemental
Shotgun + AR
Shotgun + Pistol
Shotgun + Chaos
Shotgun + Blood
Shotgun + Elemental
AR + Pistol
AR + Chaos
AR + Blood
AR + Elemental
Pistol + Chaos
Pistol + Blood
Pistol + Elemental
Choas + Blood
Choas + Elemental
Blood + Elemental
So, let's say you JUST put AP into AR + Pistol. You have a total of 133 abilities at your disposal. I'll break that down
56 for pistol
56 for AR
21 in the 3 misc trees
You can have 7 active and 7 passive abilities on your "hotbar". I don't even know how to break out the possibilities on that one.
Also, each weapon tree has passives that don't require a weapon. For Example, fists has a passive that gives you a HoT that heals you for X amount over 10 seconds for each hit you land, stacks 5 times.
So, I can use that with ANY weapon. Trust me when I say, that the possibilities are insane. I didn't know you could take passive talents and glyphs from other classes in ANYOTHER game (if there is one let me know... maybe UO?) and use them across the board.