Some of th best doodles come from drawing on line paper.

Anyways for what you have drawn here, is in my opinion quite good.

You're definitely showing a bit of your own style especially in the nonpony pictures. I'd say if anything keep at what you're doing but perhaps refine it.

As in try to get some of this done on the computer with a draw pad. I say this mainly since while a feel can be obtained from drawings in pencil and line paper.  Very rarely is it ever the true potential of the artist.

Thanks. I'll be sure to try doing it on the computer next time I get a chance.