I hate to say it but all of your stuff seems pretty much the same to me.
The only critique I could give is try different things. Try drawing things from life, try different mediums, look at stuff you wouldn't usually look at - that kind of thing.
You might not have any interest in drawing things realistically yourself but through that kind of practice you can take back all kinds of skills and ideas to what you do want to do. The wider the range of things you learn the more you will be able to express the characters you want with different backgrounds, in different poses, in different lighting, in different situations and doing things in different ways.
I'm fairly sure that no succesful artist starts out just drawing repetitive characters in repetitive poses. As far as I know even people who succeed in very specialised or cartoony styles have some background or practice involving traditional skills.
Yours isn't any worse than the art on some of the cartoons I used to watch like Butthead and Beavis, King of the Hill, or the Power Puff Girls. You gotta get your own niche and style and not try to imitate others. Maybe develop a couple characters in particular, sort of like your own icon like they did with Hello Kitty, or Jim Davis with Garfield. I mean there's always room for improvement but your art doesn't need to be of Michaelangelo quality. I like it. It would be good for a children's book illustrations.
It looks like a lot of your drawings are of 1-2 animal thingies that are repeated into most of your pictures. Try to add new ones or try never repeating the same one, at least for a while.
A lot of the drawings have no background, which makes them a lot less interesting.
The drawings that you have in that style are great, and since it doesn't seem like it's intended to be realistic at all, a lot of the inaccuracies aren't much of a problem. Are you interested in changing the style of your drawings, and is there anything you're trying to emulate?
Maybe you should try drawing /just/ landscapes so you can get better at something other than the characters that you're drawing. Maybe you should try different subject matter, or try drawing something more realistic.