Let me know which ones and I'll photoshop the better.
Also I don't think everything should be high res, high quality as manga is also about art and I tried to show a sense of what type of artwork one could expect from the manga that is being showcased in the banner e.g. Vampire Knight, Little Jumper, xxxHOLIC etc.
But on the other side I do understand that readers will be more inclined to read a manga that looks high quality rather than something that looks less well done, and if that is what MangaShare decided to do then I will try and help out. Just thought I'd throw my opinion out there as I feel its a valid point.