use A7, u can create AAA game with them easier
interesting first post.
I would suggest Unity or A7. In unity you can either script in C# or javascript which is similar to c-script/lite-c the basic workflow with unity is in smaller projects pretty good but i don't really like it if things start to get bigger.
You may be able to create good looking stuff with unity or udk in a short period of time but i'd prefer A7 since you have a lot more howto knowlegde using A7 and with it better ways to create own little tools such as optimized level/object editors for your own purpose.
I would highly recommend to use the system you know best if you are really going to start off a big project.
And for the
graphics i dont think
A7 does look soooo too bad