the OEM print bed broke for me and i ended up getting creality glass bed it works great super easy to clean and sticks well just it takes longer to heat up i would recommend getting it
The RTX 2060 will take more power and will produce more heat in a laptop.
the RTX 2060 will be 16% faster in games and will support RTX just not at high FPS in demanding games.
overclocking will produce more heat the temperatures will be higher if the laptop you are looking at does not have a good cooling solution
https://www.anandtech.com/show/13973/nvidia-gtx-1660-ti-review-feat-evga-xc-gaming/15 those are PC graphics cards not laptop ones
https://gpu.userbenchmark.com/Compare/Nvidia-RTX-2060-vs-Nvidia-GTX-1660-Ti/4034vs4037 this is a PC graphics cards and they do run faster than laptop ones