If it was a random surge I can understand your dissavowal of the wild mage, but if it was nahals you could try allowing him to use his level as an adjustable variable rather that just adding it to the surge. Also if you do this he could just use nahals to cast dangerous spells. Used properly wild mages can be very helpfull.
That which does not kill you will make you stronger.
1. I cannot stress it enough, put your 18 into intelligence. The goal of all mages in have 19 intelligence
not every mage worth his water has optimum all powerful 18-19 intelligence. you can play a decent mage with an intel of 13, 14+...just use yer noggen and you'll do fine...and don't ferget the 1st lvl spell shield, gives you +4 to your AC from the front and missiles can't get ya, very nice 1st lvl spell