Alight not a bad bunch of toys! My first suggestion would be to decide whether you want Grave Guard as your mainstay or Black Knights. Either way you will need more of either and the one you don't decide on will probably not get used. I personally like the Grave Guard but yours are hand weapon/sheild and they should be greatweapons and you would have to spend $100 to get them where they need to be. Where as your black knights hopefully have lances (Which they need) and you will only have to spend $33 to get them where they need to be at.
I would get/make another 2 spirit host bases. 3 is really good to have on your side.
No matter what you can't have enough zombies! I would say 60 is a good start but depending on how you want to run your list then you may need anywhere from 40 - 1,000,000,000 more.
Edit: Oh and the TG is bomb, I don't leave home without 2 on my side.