Well, Von Schill can kill all the mindless zombies with his pulse. He can then put a bullet into Nicodem or Rafkin.
You can use Austringers to pop him from 18 inchs away. Samael or Santiago can blast gigantic holes in his heavy hitters. Fire Wall and a totem that can cast it also will mean that you can put 4 of the 50mm templates down to funnel his forces. If your getting assaulted by hordes of critters, learn easy ways to blow away the hordes all at once.
Santiago can either rapid fire a big monster, or do his AE pulse to weaken or kill a bunch of smaller.
Samael can rapid fire down anything in a turn, no matter how big it is. 3 5/6/7 shots will put any critter in the ground.
Nino can do the blasting apart a gigantic monster or making him burn lots of cards to save them with his headshot trigger. That might actually work rather well.
Witchling handler can make your witchlings move really fast and hit hard, plus help with defense also.
Von Schill's mobile as hell, can run up and get rid of the counters/ mindless zombies because they still count as corpse counters good or bad.
Abuela can make his Flesh Construct attack the other one I believe,unless he is immune to influence. In which case you can make one of your other guys move or shoot more.
You could also bring a Freikorp's trapper and then give Rafkin a couple bullets to the face turn 1 and 2 before he can summon anything.
Witchling Stalkers are also a good thing, especially if you swarm them on him, since that 6 inch aura can really wreck with his spell summoning. If Rafkin gives models hard to wound then use Sonnia to Violate them. Once you get Sonnia's avatar summoned you should have no trouble blasting through the hordes.
And Constructs don't give counters.
Are we looking at a 35 point list?
Sonnia+Avatar
3 Fire Gamin (mostly for distribution of burning tokens,plus they explode like stalkers and cause tokens for being wounded or wounding.)
Pale Rider
Nino
Watcher
You focus on getting Sonnia out quick as possible. so you Inferno both turns, hopefully you will have a tome or two in your hand to cast the flame walls. You use the Watcher to do a stake a claim last turn for an easy 2 points.
You use the Dead Rider and nino to blast things apart when they get close to your lines. Make it impossible for him to recover the counters by putting flame walls on them. Also this list will give him almost no counters from your guys, only nino will drop one. And if you keep him the hell back like he is supposed to be you will be fine.