my lone wolf battlemage was a mistake.
At the start, being a hybrid was great: I could do simple damage in melee without taking a ton of damage (because I was using metal armor, none of that flimsy robe crap :P) and had good ranged options with spells.
Mid-game was great! Attacks started ramping up in damage, and my elemental build allowed me to explode all over the place for great aoe damage.
Late-game...well, spells were off to the side. I only used a couple of spells (Wildfire to haste myself, Oath of Desecration to buff my damage, and Death Punch because teehee) because my auto attacks would easily do 600-1000 damage. And because I was a lone wolf with good speed, I could easily do 3-4 attacks every turn if I didn't have to move (and Jahan would always just feather drop me into position). If I got myself fully buffed (Oath + Rage, 100% damage bonus) a Flurry attack would just cut anything down. Even bosses could easily have 75% of their health shredded by a fully buffed Flurry...
I wanted to respec, but since Whirlwind is not found anywhere at high levels (trust me, I've spent an hour quickloading after levelup to try at merchants) I didn't. Because whirlwind is the shit.
If you're a battlemage, use a 2hander. There is literally no reason not to. You could use 1H and a shield, but good luck finding the ability points to level armour and shield skills, alongside weapon skill, man-at-arms and your mage schools of choice. (I was a Lone Wolf and even I didn't have the points for it)
The great benefit is that melee attacks cost a lot less AP than most spells. a 2H Whirlwind attack easily does more damage than the majority of my aoe spells.
The only thing I miss is that Man-At-Arms, Scoundrel and Marksman seem to have no skills past level 10-13 (that I've found), and spells climb up to level 16 and then 18.
You have to remember that early game, undead tend to have very high resistance to most forms of physical damage, and weapon-based characters tend to feel weak.