I have a Bali Baby Breeze on its way which is supposed to be cool in summer as it's made of gauze. Apparently, they can be quite diggy if not wrapped well, but I'm hoping it will force me to become better at wrapping. If you want a wrap, something woven would be better than something stretchy (such as Close Carrier or HAB) as it has more support so you can get away with single layer carries.

Ellaroos are supposed to be quite cool and they make both wraps and ring slings.

Can you tell I've been doing a bit of research myself? lol

There is a baby wearing buy sell and swap group on FB and I've found them to be really good for advice on all types of carriers.