Plus, stats for now are useless if you have enough of them, so spending money on gear is a waste. We don't know what pvp/battle mechanics update will bring. Who knows maybe actually having non-primary stats will be desirable? Thus making mixed stat items that tend to have more total stats than single stat ones better?
Only items I get are rewards, random free drops, koban pachinko once per while, and as long as I did saw few epic items with my primary stat only, i rather have rainbow legendaries that give total more stats even being 30+ levels lower.