Don't worry about making them look too cartoony as everyone develops their own style. For instance .....

http://www.planetminecraft.com/member/varunax/
Myself
and Yourself

All 3 of us do anime skins mostly but we all have different styles
For instance Varunax used a very cel-shaded style to try to capture the genuine anime look whereas i like to gradient it a bit more.

All your have to do is develop a style you like and are comfortable with which at the same time allows the characters to be pretty recognizable.
I'm still trying to get the hang of it, but its tricky

Your skins are pretty good, all you need to decide is if your looking at adding more detail what style you want to take and try to do the best you can with that ^^

I'm really jealous of your ichigo head btw i need to make mine more orangy

I kind of wanted him in his armour body... If you have any time could you? You don't have to though