They essentially force you into their 3 roles. How can you be a battle mage, by all mean tell me?
By being a character who wears armor, and attacks with a combination of weapons and spells?
The hotkeys work fine - my current Mage/Archer has something like: 2. Bow, 3. Ice Spike, 4. Firebolt, 5. Heal, 6. magelight. Forget what's on 1, and haven't put anything on 7 or 8 yet. And going into the Favorites menu - to, for example, switch between my 4 favorite shouts - is fine, too. In Oblivion and MW, I was constantly popping into the menu to do things like drink potions, or select some of my other weapons or spells.
(Trying to remember what the hotkeys were on my Ranger. I think it was 1. main sword, 2. bow, 3. alt sword, 4. shield, 5. heal, 6. light?. And again, common shouts I selected in the favorites menu; uncommon shouts, potions, and other specific weapons/arrows/armors I used the Inventory menu.)