I know most of this thread is me posting by now, lol, but
This guy on tumblr has been uploading a metric crapton of SMUSUM concept art, and I think it'd be of your interest for some of you! Even better, you can get the full, too-large-for-tumblr raw size for your image of choice by:
1) Take off the s from https
2) Replace '68.media' with 'data'
3) Replace '1280' with 'raw
That way you can get the max full size of the ref art for your pleasure! For example
Which is of Jayce's interest ;)