I play a volcanion deck and its pretty good. As far as pokemon go i use:
4 volc ex
3 volc normal
2 tapu lele gx
1 oranguru
2 turtonator gx
If you want to mess with the pokemon list you could always switch out a volcanian or oranguru for 1 or 2 ho oh gx. Although i like the oranguru for the consistency it brings to your deck. As well as having a kiawe.
If you want the whole deck list i can post it when i get home later if you want a better idea on what a good volcanian deck looks like.