Well to begin with, Might I not suggest the Seer staff of saphery over the silver wand? The ability to pick exactly what spells you have is invaluable for making sure you get throne of vines (Mainly) and whatever else you want, though with 5 spells I suppose this is less of a problem. Im not a huge ffan of Lothern sea guard, but I see their merit. 12 Swordmasters wont last a second against anyone with a decent direct damage spell/magic missile/shooting phase. T3 5+ armor is too impressive, unless your hoping for a flesh to stone with which to buff them every turn. But even then T5 equals less wounds, but still crap armor, and lets be honest, you cant really afford to lose any from a unit of 12. And if I read that correctly the Mage goes in the Swordmasters? Bad Idea IMO. Those Bowmen seem like a bit of an afterthought to me, for their points you could just add more sea guard since 10 wont be doing anything to impressive anyways.
Also if your having problems with the army selection percentages, Try using a differant points value- 2400 seems to be the new favourite as its easy to divide and to see if your within the lines.