I've finished the game last weekend with a lv 21 kensai/mage. it was VERY hard to just get him to lv 21. my lv 13 kensai went into the asylum all by himself... but at the end, it all worked out without exp cheese. my prof.s are 4 in long sword, 5 in axe, 1 dagger, and 3 dualwielding. and i went with equalizer/axe of unyielding+3, and eventually blackrazor/axe+5. i have to say that krunchyfrogg is right about offhand blackrazor is a waste. but regardless, i find its immu.(almost same as equalizer/imo even better) very useful and the various 15% effect powerful even in offhand. axe+5 is dominating, although i had to switch to FoA on somefights, including most of the hard ones. I tried CF as offhand. its good. but i didn't like it. partly because i have a -2 penality with no prof. in hammer. partly because i dont like a hammer kensai
reactivite kensai was a... NIGHTMARE eventhough i left most easy quest behind when i went into the underdark.but at the end i pulled it out (i used up basicly all my potion, scroll, and cheesey tactics, but looking back now i think sotm's spell trap could get me further still). and after that, the game was a breeze. i almost meleed every thing there after, including boss (i like bloods

). but ill never want to play lv1 mage again...ever...
although my k/m was dominating the later part of the soa+all tob, i have to say that i "enjoyed" playing my "fragile" 130+hp lv1 mage. so my next solo would probably be a wild mage adventure. got love those cows
edit:well, since it is impossible for a lv 6 fighter/mage to kill demonknight in that first few seconds. so i used my precious mindflayer circlets

(although it did leave a bug in my mindflayer quest journal...) it worked fine but i noticed that you need to kill him within a round because after that he'll turn hostile and you'll not get the sword then. but i guess i could charm him multitimes since i never used the other 3 circlets after
btw i've never killed demonknight and only got my hlem via cheat. so i might not know what im talking about
edit2: sp immu. divination works fine with -dex

but i believe that your alignment will change if you take the evil path. nothing will stop it.