1) As said, you'd have to replace CPU, motherboard, reinstall Windows etc. Not a great idea.
2) The FX-8350 isn't that much better than the above APU (CPU part). You can compare FX-4300 to FX-8350 to get a rough idea. Yes, BETTER, but not enough to justify.
3) RYZEN?
I would WAIT another two months at least for motherboard BIOS updates, other software fixes, new CPU's etc. Then get a 4C/8T or 6C/12T Ryzen depending on budget.
Intel is worth considering but I'm waiting for the new CPU pricing, AND to see what Ryzen performance will end up roughly after some of the improvements.
(it's really about the COST savings as Intel is better)
4) Value?
Really hard to determine. Depends a lot on what games you play. Heck, if you get 60FPS on...