I'd actually only want the player mats to be larger. I mean they could easily be about the same size as the box.Copy mats at 120% (I believe up to 122% would actually work). Glue printout to the printed side of a cereal box (a simple glue stick worked for me). Cut out & round corners. Play!
Optional: Glue paper to both sides to help combat warping.
P.S. The existing mat size is indeed ridiculous but perhaps Gamelyn wants to stick to the "Tiny Epic" card size since there are now sleeves specifically for that size. Either that or it's a cost issue. Either makes some business sense but neither puts the customer experience first.