Well, I was delegated SP by a dolphin/whale (who just gave it to me) and just last month I did enter a contest to try and get some more.

I would recommend looking for dolphins and whales that are having contests for delegations. Other than that, you just need to keep working as you do and maybe someone will take notice.

In regards to curation groups- I would recommend @qurator, @appreciatoR and @thesteemengine