Captain Zipp is the greatest second master in either of his factions, with or without his totem. You get a fast, flying, independent, area denial, debuffing, repositioning, damage dealer that mostly targets Sz which no one has resistance triggers for.
In my opinion, Viktoria is the worst second/third master to hire. You're either spending 12 stones on a beater with a quarter of her card useless, or your paying 24 stones for "a master & totem".
There are certain combos that synergize really well (Dreamer/Zoraida, Asami/McCabe, Kirai/Molly, Zipp/Von Schill, Lilith/Nekima).
I personally think master costs should be higher, because the benefits currently outweigh the cost slightly. If masters were 19 stones, making ook costs 20 stones (then put Dreamer/Lynch/Viktoria/Anya at 14 costing 15), we would be fine.