I've played with several of them, but I don't want to dedicate the time only to find out it won't work for me.

Here are my requirements:
I am going to have a 3-sided cocktail cabinet. All three sides are unique. I will play horz and vert games both. Depending on the controls needed, some vertical games will be on one side, some on the other.
Most horizontal & 2 player games will be on the long side. For instance, one side is a 4-way joystick and a few buttons for classics, the other short side has a spinner and analog joystick for Tron or Tempest. I would want the game rotated to the proper side for the controls I pre-choose. I will not be playing any 2-player cocktail games in "cocktail mode", as I have no 2 sides with identical controls. Screen flipping for those is not important. Now, I know I can pre-pick the direction in MAMEUI and save it - it would be nice if a front end would honor my selection. Or if the FE has a better way to do it, that is fine.
Niceties:
The FE can be used from any side (might be hard to do since some joysticks will not all be player1-joy1)
Would show standard MAME panels, marquees, etc.
Videos showing the game in action (ala Hyperspin....probably others)
And here is the killer feature I would love:
Something that would show a JPG of my control panel before a game is played and "highlight" which joysticks and buttons are needed to play it. This would be something useful for people who have guests over, or just have a Frankenpanel in general.
I realize most of my requirements probably eliminate the desire for it to be setup easily, but that is also a nice-to-have.
Don't care:
If it costs money. I just want the right FE.
So what is my front end?