Crossbow Success!

To create a character that is successful with a crossbow, choose basically any race of character.
Start with the following innate attributes:
Strength: 70 (for lugging around all those heavy crossbows and armor without being vastly overburdened.)
Endurance: 60 (If you have no stamina, how are you going to cause damage? How will you survive without a high enough health level?)
Coordination: 100 (It adds damage as well as skill in your crossbow skill. Self explanatory.)
Quickness: 40 (Contrary to popular belief, You do not need quickness for a high damage or skill in Crossbow. Or even Bow, for that matter.)
Focus: 50 (Needed to make quarrels and elemental oils, also needed for a decent healing skill.)
Self: 10 (You won't need to cast spells right off the bat!)

Train and Specialize in Crossbow, train Alchemy (If you're Undead it's a racial skill, or if you're Empyrean and switch racial skills.), Fletching, Healing, Melee Defense, Arcane Lore (If you're Empyrean it's a racial skill; or if you're Undead and you switch racial skills.), and Item Enchantment. Item Enchantment will be especially low as you have minimal Self, don't worry about that.

As you level up, pour points into item enchant and self until your self is 50 base, and your Item Enchantment is about 100 base. Then you should be able to cast portal spells while buffed with minimal fizzling. from there, it's your choice.