There's no real imbalance in Malifaux, so even though Criid had some tricks against Arcanists (she has some neat anti-caster stuff if I recall) that's not making her an auto-win. I can say she has a fun crew to play, Hopkins is awesome in both model and shooting ability, and the Witchlings are cool too, and be surprisingly nasty little blighters if they get into combat.
Can't really comment on Marcus's crew as I've never really looked at them, but a quick look reveals it can do a 34-42 Soulstone range dependant on upgrades, and Sonnia does 27-38
SS, so while you might have to take less upgrades on Marcus, there is scope to play the same points value for both. I've found that a few
SS difference isn't really am issue when starting out anyway.
Check here for loads of Malifaux info:
http://gmortschaotica.blogspot.co.uk/p/unboxing-malifaux.html
Welcome to Dakka as well!