If you haven’t already tried, I would try diyaudio.com - a lot of designers hang out there.
Nice to see so many bipolars in use rather than all FET (personal opinion only) 
My own thoughts - build it, listen to it, and tune it.
Partly because deep analysis of analogue circuits is beyond me now, and partly because
the lowest THD and whatnot don’t always sound the most musical and enjoyable to audiophile ears.
It would be good to actually listen to multiple iterations and (if you have the kit) aalyse the distortion etc. after you have listened to it.
(and please report back!)