I want to get a better CPU. Ideas?

You need something a bit nicer than the FM2+ platform. Ryzen 5 would do fine and it's cost effective.

PCPartPicker part list: https://pcpartpicker.com/list/mFMF9W
Price breakdown by merchant: https://pcpartpicker.com/list/mFMF9W/by_merchant/

CPU: AMD - Ryzen 5 1400 3.2GHz Quad-Core Processor ($156.88 @ OutletPC)
Motherboard: ASRock - A320M-DGS Micro ATX AM4 Motherboard ($49.99 @ Newegg)
Memory: G.Skill - Ripjaws V Series 16GB (2 x 8GB) DDR4-3000 Memory ($124.99 @ Newegg)
Total: $331.86
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2017-08-06 19:43 EDT-0400

That's the minimum I'd go for. Preferably I'd rather see you go with something more like this...

PCPartPicker part list: https://pcpartpicker.com/list/npZjCy
Price breakdown by merchant: https://pcpartpicker.com/list/npZjCy/by_merchant/

CPU: AMD - Ryzen 5 1600 3.2GHz 6-Core Processor ($197.88 @ OutletPC)
Motherboard: ASRock - AB350 Pro4 ATX AM4 Motherboard ($61.98 @ Newegg)
Memory: G.Skill - Ripjaws V Series 16GB (2 x 8GB) DDR4-3000 Memory ($124.99 @ Newegg)
Total: $384.85
Prices include shipping, taxes, and discounts when available
Generated by PCPartPicker 2017-08-06 19:47 EDT-0400