I have a 4790k now (and a gtx1070) that is starting to struggle with gaming, and I am looking to upgrade. I dont play too much games anymore so I have been looking at buying used parts to keep costs down. I have found the 10700k for decent prices but I have seen that the newer 13700k and 14700k have a bit better performance (although they will be a bit more expensive). I will probably pair it with something like a GTX3070ti, and I play on 1440p. Should I spend the extra money on the newer CPUs or will the 10700k work well with a good GPU?
You have a massive leap to jump into. If you want to maintain the i7 tier, I highly recommend 13700 or newer. You will find great deals out now, especially if you have a Microcenter near by. Keep the 1070 for now, you will get a very nice fps boost with the CPU upgrade. Then later decide if you truly need a new GPU or not.