I love theme parties!! I would go for that as sometimes titles like housewarming scare guys away! lol
Everything depends on how much effort one wants to put in. You can go from having friends cook to having ti catered. It all depends.
I would suggest your friend register as I had a housewarming without it and people had no clue what to get me.
As long as yo uhave good music food and drinks it should be a blast!!!!