I would put in Exquisite Blood into the main board. And if you have the budget put in Urborg, Tomb of Yawgmoth. Profane Tutor is also a good cheap tutor.
I hope this helps, have fun!!!
Thank you for the tips, it's very appreciated! I was also surprised as I didn't know that his was also a forum where you could comment on decks.
I guess that if I would add
Urborg, Tomb of Yawgmoth as you suggest, then I should also be swapping out a few of the Swamps for cards like
Cabal Stronghold and such? After I got a hold of
Cabal Coffers I went into a direction where there are quite a few X mana spells that are used to directly damage other players.
Also, if someone else is interested in a deck like this - then there are also these tutor-like cards that are really cheap but also really good:
Dimir House GuardBrainspoil