I've been experimenting with a self-mill dredge mechanic that is working pretty well. It might not translate to higher power environments though. Essentially, it's a control shell with things like
Stinkweed Imp,
Hedron Crab,
Dakra Mystic,
Darkblast, lots of card draw (
Frantic Search rocks here like super hard) and some removal. Once you get cards in the yard, that powers delve cards (black/blue have a ton -
Tasigur is custom build for this deck) and it can power graveyard recursion.
Haakon works good here.
Dread Return is great because if it gets dredged the flashback can be triggered - really nice later in the game when crab, mystic and imp can all be sacrificed for a big nasty finisher.
Skaab Ruinator is just the right power level for this too. He's strong but exiling three creatures is a lot and you will only be able to recur him a couple times typically. He also dies to a lot of black removal so can be dealt with by your opponent. But if he can't be killed, a 5/6 flyer does a ton of damage.
This pairs nice with green for the regrowth style effects.
Genesis in particular since you want it in the yard anyway and it gives you another path to get cards back from the yard other than reanimation effects.
I did not like milling my opponent. It's not a fun mechanic because it's either too good or not good enough and just pointless. But self mill is a different animal entirely because there is a lot you can do with it and you always feel like you are building towards a goal each time you mill yourself. To some extent it's like a lottery too… ooooh, what did I just dredge?!.