Upgrade of electric scooter (esc, motor, battery)

Hi, I bought a Kingsong e-scooter (800w motor, 750wh battery) about 2 years ago and have been using it a lot. I somtimes use the scooter to get up mountain roads when I am on tripps. I have to take many breaks because the esc gets too hot. now I want to upgrade it so that it can handle all kinds of slopes with some speed and maybe get a little longer range. I had appreciated the help to find the right parts I can use. I thought I could use the motor that is on the scooter now, and put it in front, and buy a new more powerful motor (around 2-3kw) that I can put on the back of the scooter. I have looked at flippsky`s esc or vesc but do not know if they are suitable for this purpose. when it comes to the motor I need something that pulls well on the slopes, it does not have to go faster than 40-50kmph. does anyone have any ideas about some good hub motors that might suit me, and can I use flipsky’s esc / vesc or is there something else that might suit me better. I will make the battery pack myself, and have some experience with this. my budget is around $ 500 (excluding battery pack) thanks for all the answers!

flippsky esc/vesc: https://flipsky.net/collections/electronic-products/products/dual-fsesc6-6-based-upon-vesc6-with-aluminum-heatsink-1

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