Dunno about this. I'd rather have a warlord for the General, and a couple of Warlock Engineers as the magic. Skaven Magic is nice, but not overwhelming. In low point games, don't buy the expensive and dangerously vulnerable point sink that are Grey Seers
Add another Chieftain. And you should have a magic banner here. Storm Banner is best if you face shooty armies.
1x40, 1x35 rats here.
MORE. Fifty to a hundred! With the cheap Chieftain for some spine!
Remove. Not worth the points spent elsewhere. If you insist, take 20 - free up points for above. Allows you to keep the 3rd Ratling gun the consolidation above removed.
Good. It gets Great when you add Squeel Gnawtooth.