I would not recommend wasting money on getting another 4th gen Intel CPU, especially since your only "upgrade" would be to get a K series to be able to overclock it and get more performance out of it, which would require getting a new motherboard anyways.
To get more performance you need to replace the CPU with one that has better performance, or can be overclocked to have better performance, and get a motherboard to go with it since any worthwhile upgrade will require a new motherboard regardless.
If you want to stay with Intel you can always upgrade to something used that isn't the newest thing on the market but is newer than what you have and is a K series CPU along with a Z series mobo to go with it for overclocking, otherwise, Ryzen is where it's at for you, and you don't necessarily have to get the latest and greatest, you can opt for saving a little bit of money and get used 1st or 2nd gen Ryzen with a mobo from somebody who has upgraded and is selling off their old parts.