Maybe. I like smf's focus on board/subboards, which discourse doesn't seem quite as keen on (?) (of course, this is also because I am used to it, eventually I would get probably used to discourse's systems anyway), and a dealbreaker is how easy/hard it is to change permissions and such.
EDIT: Looked a bit more on the features, and it does seem pretty nice actually. Also, not too good at this stuff, but would it be possible to use
https://meta.discourse.org/t/official-single-sign-on-for-discourse/13045 to merge forum and game login?