How restricted will Races be when choosing classes?
It's all alignment based. Which race/class combo you pick is based on your alignment chosen from one of the 9.
Will there be some classes that are only available to one or very few races?
Nope. A race just might suck at a class.
How restricted will Races and Classes be when combined with Kingdoms? ie Could certain classes only come from certain kingdoms? Perhaps a magic user trained in the east would have slightly different talents than one trained in the south, no matter whereabouts they move to later in life?
At game start, they won't. I'm investigating a way to have 'knight' be both dark knight and paladin, based on your aura with different skills. Same with a priest.
This requires some custom coding, and won't likely be address until after 1.0 launch.
However: from the get go, every class will have a prime and a second stat, which almost all their skills will use for effectiveness. For example: a thief has dex/int, let's say. High int means they maybe able to lay traps or use poisons more effectively, but a high dex means more powerful circles/backstabs. A priest might be wis/int, with their healing spells being wis and their damage spells being int based.
This will allow for lopsided races (giants, sprites, etc) who are 25 stat heavy to excel at only one aspect of the class (without SERIOUSLY sacrificing their character's other stats) and allow tweeners to 'split the middle' as they see fit.
So a dwarf soldier might be great at tank, a giant great at damage, but a human can split the middle.
Stats will matter in this game, as they will set the 'floor' for the bonuses to *add* to. This means skills + stats (and racial bonus) will be used to calculate the base floor (whether its damage, time for DoT, success for dodge or swim, etc) and then the buffs (spells + equipment) get added to it. So a giant will receive no more damage boost than a sprite in terms of equipment and buffs (a few exceptions may exist), it's just a giant's floor will start much higher.
The floor is a 'step-linear' (1-11 is penalty - aka -1, 12-20 is 'normal, aka +1', 21-24 is +2, and 25 is +3 currently). Things like 'two-handed' on a sword don't buff YOUR floor damage for melee. It boosts the *weapons* floor damage. This is then added against your floor damage. Then buffs are added atop this.
So in this, what determines melee damage?
A level 50 two-handed heavy sword has an accuracy, speed, and damage value associated with it. It also gets a 25% two handed bonus. It's level + damage + size + type of weapon (heavy sword) + enchantments on the weapon determine the floor damage of the weapon. Then multiply it by condition/2 (so at 50% condition, it deals 25% less damage).
Then that # is taken against your skills (sword specialization proficiency level, enhanced damage, armor penetration - if applicable), your size vs the weapons (if its smaller, you lose damage, but gain accuracy, bigger you gain but you lose accuracy which is calced before hand in the hit roll), your base strength/5 rounded down, and then your affects.
Currently there is no critical roll. I'll be introducing critical hits as a function of cha + int/2 to spice things up after I can get a good stable baseline, reliable melee dps going on.
I hope that explains a bit why classes are going to be the way they are. Also, I do plan (post beta) to allow characters to 'remort', and redo their stats after they hit 50 at a high cost, so they can 'change' their focus within the class. Currently I do not plan for class changes to take place, but in the distant horizon am considering that level 45+ characters will be able to 'sub focus' in their class for an additional few skills.
Example: a sorc at level 45 can choose to be: elementalist, divine inspiration, or battlemage.
An elementalist might get a few low level warlock AOE or range spells.
A divinely inspired mage might get heal serious, cure blindness, and a few other low cleric ones.
And a battlemage might get whips, a castable bash ability, a weapon damage boosting spell, and a defense spell etc
These are just examples, and these might be a year away, but that's vague outline I'm aiming for the evolution of the game past the basic 4 classes for open alpha, then the 'base 10' for open beta.