I think that Leo would most definitely be a RainWing! And this is what I think he'd look like. :) 

-Traits they have in common: Laidback (for the most part,) fun and excitement-loving. 

-He would be an absolute MENACE with camouflage scales (both in the sense that it would drive his brothers crazy and against while fighting against enemies)...and that's something I'd LOVE to see! XD  

-Ooooo Leo with venom is a cool idea as well...but I think his main go-to would be camouflage...thoughts...?

(If you don't already know this about me...he's my favorite... :D)