Wismerhill was a little bit to paper thin for my taste, the guy is supposed to be ...well, strong.
The files are in :
\Black Moon Chronicles\BlackMoonEN\Maitres
there is a file called "wis" ,open it you can change wismerhill's base life, his strengh and other stuff like how much life and strengh he earns each level.
You can tweak other units by going to their specific files.

AVE TENEBRAE !!!