Well you just have to play at lvl 40, stuff means nothing at this lvl and you will do almost same XP and Marks as lvl 50 arena and get ilvl 70 stuff in 150-200 matchs.
And then you will be able to play VS R30 (or at least play more than 10 sec),

Or you can find 1-2 mates and try to play as a team and beat every useless R30 in solo Queue

Or you can wintrade like everyone and get 120 xp and 180 marks every 5 min.

Each time i get in arena after waiting around 45 min and see mates with around 3k HP and 0 moral at lvl 50 i just want to kill every lalafel in the world

PS : Thanks to SE, sometimes after waiting 45 min, 4 R30 are match together vs 4 useless pve stuff, allways fun to wait 45 min + 1 min to play around 20 sec.