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

Use A7 for your game prototype and make sure the models look great in a testlevel. It is easy for you to create a prototype using an engine you are familiar with.

Learning a new engine, new language, new workflow, ... for your first big project is not a good idea. If you switch to another engine, it might take up to 6 month until you know how the system works internal and what is the best way to develop a given feature.

Spend some time for tweaking the graphics and tuning the engine after you have your prototype up and running.

You should be able to export the models for use in other engines, too. Check these models in other engines and compare the visual results in terms of quality and fps.

ihr könnt auch deutsch antworten, dann versteh ich euch besser.. ich schreib nur englisch für unsere englischen freunde hier ^^

thx for help.. i´ll ask my team what they hate so much at A7 when they come onlien again ( or tomorrow.. when they come to my birthday party ^^ )

Überleg doch mal, wie viele Modelle und Texturen dein Team erstellen muss. Nachdem die ersten statischen Modelle stehen, kannst Du bzw. der Leveldesigner im Team anfangen einen Testlevel zu erstellen.

Mach den Vorschlag, dass ihr euch eine andere Engine sucht, wenn dieser Testlevel in A7 nicht der Erwartung der Mehrheit des Teams entspricht.

happpy bday espér