For devilchu you should have usedthe largest wing on the left side and the small one on the right side
The tail looks really square, try adding some pixels at the side ends ;D
Revamps are cool, i remember doing them and it was so much fun
But the R/B ones are the easiest, try revamipng a G/S/C one ;D
It's harder because the gbc had a really low palette restrinction, so you'll have to extebd that pallete and figure out where the new colors would be.
The outcome of G/S/C ones is awesome