Is a lighter or heavier yoyo better for horizantle play?
Basing on my own experience:
To start, I’d say a heavier one helps you follow the momentum of the yo and get solid basis. Once you’re comfortable with that, I think you can put one step further and take a light one to work on speed. Then you do following what you’re more comfortable with.
But I may be wrong, this is just how I did myself.
eh try a heavier yoyo to get started then get a yyj meteor 
It has more to do with the shape of the yoyo. Look for one with a narrow profile and a sharp wing shape with plenty of rim weight. Any of Mickey’s yoyos are pretty much the best for this. (Speeder 2, Phenom/ism)
Personally, I haven’t used anything that handled better horizontally than the Super G, which is toward the heavier side. But I think that more to do with the shape and distribution of the weight.
some light yoyos handle well( maybe, but i’m not really sure)
what i am sure of is the shape really plays a BIG part in horizontal play. For example, a Protostar would handle horizontal play a lot better than a counterattack. Material is a factor too(not as serious as shape though). A rockstar would play better than a protostar(less friction between metal and string than plastic and string).Ok, you get the point, the less friction the better.
I like my Dietz with the ultra light side effects which makes it like 62 grams for horizontal