Hey Hippo... YOU asked... what did you expect... glowing reviews? If you don't want anything but positive feedback... ask for that only. Anyway, you should see some of the amazing stuff posted in the artwork section from time to time... and a lot of those guys are looking for honest feedback. Even when it's REALLY good, there is usually room for improvement. I'm not saying people can't like it... I just feel that it's lacking personality. After all, it's going into an arcade cabinet. Why not go over the top. Instead of using the LAME logo... (which I've ranted about before) Use something that's more personal to you.... either themed with old arcades in mind, your own personal theme, or themed on a specific game you like, or a system, or other hobby / interest you may have. I'm not really into people just putting Mario and Fighter dudes, and 200 little sprite or box rips all over their front end skin, but I just think a bland picture of lightning with a MAME logo is not as good as you can do.
The important thing is... that you feel strongly that YOU like it. If YOU like it then... that's cool. If you want to know what I think (as your posting says) I think you can do better if you put some thought into it.
Anyway, don't feel bad. I'm a professional designer... I pick apart other designers all day, and they do the same to me... it's a habit. If we're talking about REALLY critiquing... that can get pretty rough. I had to stand in front of a room for 3 hours once while a professor explained how bad a particular project I submitted was. I've gotten better since

That being said... welcome to the board

and I completely agree with RayB on all counts.