These bulldozer/piledriver based Athlons run really, really hot, just like everything else that is based on that architecture. Both my a6-5400k and 760k, at stock clocks, idled between 30-40C with an ambient of -7C, with the older Hyper tx3 strapped to them (not the evo, and not the new one). Under full load, they'd quickly shoot up to about 65-70C on the same cooler with the same ambient temps. If you're not running the APU in full (if you have a discrete GPU), temps shouldn't be nearly this high, with idle at around 23C (same -7 ambient), under load at about 55. Long story short, I put my computer outside during a typical upstate NY blizzard at 2AM and ran benchmarks, for fun. I don't live there anymore, so I can't do further sub-zero air cooling tests.
Your temps honestly sound about right for a case with horrible airflow and a garbage cooler, especially if you have a hot AF AMD GPU sitting underneath it (I know all about it, had a heavily overclocked HD7950 under my 760k for a long time). All I can say is to get rid of the drive cage, get more bigger fans and move more air, and get a proper CPU cooler. I know the wraith is plenty better than the old stock cooler (I have a couple of nice paperweights lying around, hehe) but nowhere near as good as this old $15 Hyper tx3, let alone a T4 or Hyper212 or anything else. Definitely don't overclock that 880k until you get a proper cooler, but once you do, have at it.
TL;DR You require additional fans. And a real CPU cooler.