Right now the best examples are in the tests and also in the talk
slides (
http://tinyurl.com/gxp-oscon-slides). We've been meaning to
write some better examples, but unfortunately haven't had the time.
Some of your requirements seem very compatible with GXP: it isn't
coupled to servlets or the filesystem at all. The one thing you
mentioned it might not be a great fit is dynamically compiling
templates. While GXP does have a dynamic compilation mode, it is
really intended for development, not for swapping out templates in a
production system. A lot of GXP's benefits come from compile time
checking, some of which comes from the GXP compiler and some of which
comes from a Java compiler. I don't want to discourage you, but I
don't want to give you false hope either.
Anyway, if you do try it out we'd be interested in hearing what works
and or what doesn't work. And of course, if you have any other
questions feel free to ask them here.
Thanks