I think that it is totally fine for an IPS monitor, it is not that bad. My dell light bleeds too and I rarely notice it in the real world usage scenarios. Maybe other owners of this model can share their experience.
I think that if you go AMD way, it is better to get FX-8320 and overclock it. Having email@example.comGHz and R9 290 myself, I can run anything at ultra@1080p just fine. There are few games that utilize only 1-2 cores and GPU is bottlenecked by FX-8320. CPU overhead issue with AMD graphics drivers amplifies this effect in AMD CPU+GPU combo, however you still get acceptable performance in those games. Because of this, I think that the best combo would be Intel cpu + AMD gpu or AMD...
So basically the problem is with running FL studio? I've had the same problem and switching to asio4all driver in FL studio solved it. I have an FX8320@4.6Ghz, everything worked fine when it was running @4.2GHz.
Here is the guide.
If you already did this and still experience performance issues, then overclocking might help but I wouldn't expect miracles.