What's the smartest way to upgrade in the near future?

Games are either cpu limited or graphics limited.
You should find out which for YOUR games.
Here is my stock approach:
Some games are graphics limited like fast action shooters.
Others are cpu core speed limited like strategy, sims, and mmo.
Multiplayer tends to like many threads.

You need to find out which.
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To help clarify your CPU/GPU options, run these two tests:

a) Run YOUR games, but lower your resolution and eye candy.
If your FPS increases, it indicates that your cpu is strong enough to drive a better graphics configuration.
If your FPS stays the same, you are likely more cpu limited.

b) Limit your cpu, either by reducing the OC, or, in windows power management, limit the maximum cpu% to something like 70%.
Go to control panel/power options/change plan settings/change advanced power settings/processor power management/maximum processor state/
This will simulate what a lack of cpu power will do.
Conversely what a 30% improvement in core speed might do.

You should also experiment with removing one or more cores/threads. You can do this in the windows msconfig boot advanced options option.
You will need to reboot for the change to take effect. Set the number of threads to less than you have.
This will tell you how sensitive your games are to the benefits of many threads.
If you see little difference, your game does not need all the threads you have.



It is possible that both tests are positive, indicating that you have a well balanced system,
and both cpu and gpu need to be upgraded to get better gaming FPS.
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On the cpu side, your only option is for a FX-8350 or such.
You get two more threads, but no increase in performance per core.

A cpu upgrade that is meaningful will require both a motherboard change AND a ram change to ddr4.
If buying new, look to the latest gen options; you get more for your money.
Go canon lake for intel and better performance per thread.
Ryzen is a decent option if you run multithreaded batch apps that can make use of many threads.
Only OK for gaming.

A graphics card upgrade is easy.
It can easily be transported to a new build.
Use tom's gpu hierarchy chart and look for at least a three tier upgrade.
http://www.tomshardware.com/reviews/gpu-hierarchy,4388.html

That is probably a GTX1060