Great job! Self-validation is definitely the most important thing. I don't know if it would suit you, but when I feel like I am finally in state of creating something really good, I am making a full art, like completely with some plot (not just flying heads), full coloured, etc. If it works out, the self esteem is hugely boosting Sometimes it doesn't happen, then you just leave it for later, but it is the attempt that counts, you can clearly see what works and what doesn't, or maybe you would prefer something different in the end.