I would say a Poison/Steel one for me.

Great question! A Poison/Steel typing like you suggested would be an interesting concept, and I'd love to see the character design for that. Perhaps it would be a mix of purple and grey? Metallic and toxic? It makes me think of Honedge's sword design, except that I'm imagining a Steel assassin with poisoned blades instead of a Steel Ghost like Honedge's typing. It would be interesting to battle with, having a super resistance to Bug, Fairy, and Grass -- kind of like an "I don't like your flower garden!" Pokemon. The garden Pokemon could then stage a mass revolt, where they call in the reinforcements, who dig and create massive earthquakes to stop the Poison/Steel type, since it's very weak to Ground moves. It would be like preparing the soil for new plants later. I wonder if this could be a movie? Maybe the movie idea is silly, but the dual-typing's great! What do you think?

I can see myself with a full team of Ice Fairies! Also, I know it sounds weird, but I'd like to see a Fire Fairy design, too. One of the characters in Generation VI games asks the player, "How can I make my fairy Pokemon get along with fire types?" Maybe a dual-type would be a peacekeeping sort. In terms of non-Fairy typing, I'd like to see a Psychic/Electric type who combines brain-waves with shock-waves! It seems like dual Psychics are popular, but I can't find any examples of an Electric mix.

Thanks for the great question! I'd like to see more ideas.

I hope for more fairies... what about dark/fairy? In legends and stuff, fairies aren't all about those cute winged things. There was a great lack of fairy types in this gen, and they weren't all that much useful in general.

The main problem (I think) about the new fairy type: Oh, this one is cute, let's make it fairy. Eh... Tons of wasted potential. What about Gulpin/Swalot? And all of those you have mentioned, even Rapidash! I'm quite confused that mega absol isn't fairy too... or at least flying. Belossom? Regigigas?

Still, I'm still hoping for some kind of creepy fairy type. Ghost/Dark/Poison or something.

I hope to see a proper water/fire type too, the last one was disappointing, even if never released.

I was kinda thinking it'd be having a mix of gray and green. I think a Poison/Steel type would help balance out the poison types as well as a Psychic/Poison type, since it would cancel its' weakness for Psychic. I also like the other type ideas you've listed as well.A Dark/Fairy sure would be nice as well, especially if it is a legendary Pokemon.

Fairy/Fire I think that would be interesting.