I think the size is fine. The feet and the arms are pretty wrong though. The arms should be longer, unless he's amputee, I always thought more amputees should be in video games.
Feet don't point that way. They usually make that L shape, one foot points forward the other to the appropriate side. You should try positioning yourself like the character. If it's comfortable you to pose that way then it's probably a good pose. Probably every really talented pixel artist here and a lot of decent pixel artists here act out animations.
The brown costume needs more contrast, the green palette probably needs more contrast too.