70C is perfectly fine. Our workstation’s Ryzen 3600 could even throttle at 95C using the stock cooler if we run stress tests. Idle was around 50-55 deg. If we use design tools the temps are around 80+.

So I think don’t have to worry too much about the temp and keep the money to upgrade other things. My suggestion is to fill up that M.2 slot with a NVME drive.

Normally the thermal paste comes with the cpu cooler right? I think I will buy one of these later on

Thermalpaste i would say Noctua NT-H1 also good enough already. Thermalgrizzly Kryonaut is very pricey. I dont even see noticeable improvement in a hot gaming laptop compare to the much cheaper Noctua