it would be easier if you had something in specific in mind. its like asking us - can you tell us everything you learned from life.
things i can point out:
this should be portrait, cropped clean on the edges and in focus. this won't print as it stands now because they have printing standards. you need a better description, google and people see that. only 3 tags won't attract others.
if this were for sale - it would never print due to the watermarking.
this is not all that sharp up close and it looks crooked. you have no keywords at all. not many will look up - portraits art paintings - and the description? you want to tell people what we are looking at. but these images should be scanned in.
this shouldn't be sideways, its noisy, not sharp and there is a big crop mark at the bottom (right side of this)
you should have a bio explaining yourself, this is for google mostly. you have to be careful selling famous people because the estate could come after you. and i know the jackson estates especially does that. selling on the premise of someone famous, well it should be your own creation and you shouldn't be riding off others fame. just something to think about. i don't know of any that were caught off hand, but that doesn't mean their won't be.
you have to advertise yourself - after you fix all the images you have there. if you have more work post more, your in only one group, join more. beyond that i don't know what else you want. though also remember even though they might be famous, there are a limited amount of people that actually want michael jackson work on their walls. newer people may not know who he is and wouldn't be a huge fan. and huge fans already have their walls filled with his stuff.
---Mike Savad
MikeSavad.com