person at the counter could be further back, currently not allowing enough room for the body to exist, the purple coverings of the wheels don't really make sense, the cup isn't isometric at all, there are a few areas where your iso lines jump from two pixels wide to one pixel wide, creating a jagged area, uncertain of the lightsource, the wheels aren't quite smooth enough, etc.
this is why i advised you focus on a single submission. now, rather than having one piece that makes it into the challenge/gallery, it's more likely you'll have three pieces that get sent back.
The man looks super thin. The lemonaid bottel looks a little more 3/4 veiw instead of iso. Its cute, I like the straw. My personal favorite in your "series" is the golf kart though.