I like it. It feels like how a PrC should be, specialized. I think it could use a small buff though.

First, may I suggest swapping the first dead spellcasting level to 1st? I think it would be a nice way to avoid your class from being just a dip PrC. You eat the dead spellcasting level right off the bat so you don't feel obligated to jump out as soon as it shows up.

Second, I think dead spellcasting levels should contain the most powerful abilites of the PrC. Those levels should have something more... I don't know. Bonus Feat is nice but not good enough IMO, would be nicer to switch it for something else.

Also, the PrC gives me the feeling like it wants to bash undead skulls in. I think it might benefit from full BAB progression.

Good work so far though!