Stuff: Nice work. Since you enjoy pixel based work
and games let me suggest allowing GOG to give you some artwork assignments. Every week GOG releases two or more games. You never know till release day what games are going to be released . . . usually anyway.
Find cover images for the releases and remove old publishers, ratings, media type, etc. The cover images can be found on MobyGames or just by Googling for them. Some games have several different covers which would be a bigger challenge to edit all versions. Every game uses a different "type" of artwork, some realistic . . . some cartoonish.
Bring the finished cover image up to 300 dpi @ 3" x 4" with all offending image data removed. You can use multiple images, edit the area directly, clone image data, use vector tools to redraw . . . anything you want . . . just have the finished image look as if the artist just finished the artwork and the marketing dept has not gotten their hands on it yet.
This would give you some interesting random assignments and combine two of your interests. See attached for an example of what I am suggesting . . . =)
Edit: Finding high quality images to work with will be one of your biggest challenges.
Thanks that seems fun, and whoah, there are a lot of new tips O.o I will check them out later (in practic phase)