I can offer some help here.
Warlock engineer -128
lvl 2
warp energy condensor
pistol
I recommend making this guy a level 1. He will default to warp lightning so you will always get it, and then you can take the condenser to buff the spell and maybe get power dice. The pistol is cool too. But the super efficient will argue its worth.
Chieftan -72
bsb
shield
Because this
BSB ha no magic banner, he should have more to help keep him alive. Maybe an enchanted shield or a ward save?
clanrats (25) -202
shields and spears
musician and standard bearer
poison wind mortar
clanrats (25) -189.5
shields -12.5
musician and standard bearer
poison wind mortar
clanrats (25) -189.5
shields -12.5
musician and standard bearer
poison wind mortar
I like the clanrat blocks and weapon teams. However this list depends greatly on the weapon teams for killing output. If something goes wrong, and with Skaven, something always goes wrong, you will be left with clanrats to do the dirty work. And that's usually rough.
gutter runners (5) -65
slings
I feel the gutter runners are too small to be useful. With multishot from slings, you'd have 10 attacks at BS3 -1 assuming no other modifiers. I feel that these guys are hurt by their small numbers and should either be fleshed out to 10 or ignored. In a bigger game, add poisoned attacks to these guys so that the
BS of the unit wont matter as much, since you will hit and wound together on the poisoned roll of a 6 to hit.
Doomwheel -150
Doomwheels are awesome.
it comes down to 998
Good luck.