We know that we are limited to six skills hotkeyed - which is a good thing because it advocates careful planning and avoids the tradition of having untouched abilities on screen and keyed. However, this may be difficult to implement - because it could advocated a "mother of all combinations" - forcing you down a particular path. I would quite like to see it handled as follows.
(I think the classes should be fairly basic to start: Warrior, Thief, Mage, Battlemage, Nightblade, Rogue)
Warrior classes:
Their six hot keyed abilities can be chose as follows (assuming heavy and light attack don't count):
STAMINA GOVERNED SKILLS X2 - (Agressive (e,g. Sword sweep), Passive (shield wall)
HEALTH GOVERNED SKILLS X3 - (Passive (e.g. AOE buff And self buff)
MAGIKA GOVERNED SKILLS X1 - (Passive (e.g. Basic self heal in combat (akin to healing in Skyrim.)) or a basic aggressive magic spell (flames))
Thief Classes:
STAMINA GOVERNED SKILLS X2 (Agressive (e.g. Dagger flurry), Passive (e.g. Stun/disarm enemy)
HEALTH GOVERNED SKILLS X3 ( Passive (e.g. Reach into an enemies' inventory and steal a health potion, Reave - take health and convert it into stamina to fuel a flurry)
MAGIKA x1 - (Passive - Invisibilty)
Mage Classes:
MAGICKA GOVERENED SKILLS x6 - (2x aggressive (e.g. fireball and flames) 2x Passive (e.g. Stone flesh, Paralyse. 2x Utility - e.g. group heal AOE)
Nightblade:
STAMINA x 2: (Agressive thief skills)
MAGICKA x4: ( Illusion X2 - Alteration x2)
Spellsword:
STAMINA X 3 (2x aggressive warrior skills + 1 passive)
Magicka x 3: (2x Restoration, 1x Destruction)
Rogue;
Stamina X3 ( 1x Warrior aggressive (sword flurry), 1x Thief aggressive and 1x passive from either)
Magicka X2
Health x1
In other words, the abilities that you can choose are resticted to a certain amount from each attribute and skill. This ensure people don't dump the most overpowered from each category into 1 build - at the same time keeping combat fresh and allowing replayability.
In terms of how these'll be mapped into the keyboard and mouse - I'd quite like:
Heavy attack - Hold Mouse 2
Light attack - Tap mouse 2
Powers - 1 through 6
Those are simply my thoughts - anyone feel differently.