I also had problems with the bed level probe. It is rated 10-36V and Hiprecy tries to run it at 5V. Actually it is worse: 4.6V as there is a Schottky diode in series of the 5V which I think is installed to isolate the 5V from USB. In here the V1.4 board differs from the V1.3. One of the reasons I requested here the V1.4 schematics added to Github. My solution: I created a small circuitboard with an optocoupler which allows the bedlevel probe to run on 24V and safely interfaces now with the logic board.
The cooling solution from the Sakul forum is looking good and should be sufficient I think. I used the solution from Mr Junior Barnes at Thingiverse and also his firmwares which work fine for me.
https://www.thingiverse.com/junior_barnes/collections/hiprecy-leo-mods
The TMS 2209's have a lower RDSon and therefor should dissipate less heat and are worth trying in this case. I also have a set present and I am curious if they provide also better print quality. But currently my Hiprecy Leo is defective too. The Y direction is behaving weird. The crash detection doesn't seem to work anymore - the Y stepper wants to push the mechanical endstop from the rail or something like that. My last prints were shifted in Y and an autobed levelling for example finishes halfways in Y direction at the moment. I replaced the Y stepper driver but that didn't bring a solution. I am having an Fysetc S6 V1.2 32bit controller here which I want to use in my Hiprecy LEO but I am unable at the moment to compile the LEO firmware for it - that is why my request here at the forum for help. I ordered a new Fysetc F6 V1.4 controller and waiting for that hopefully that will cure the Y problems (which I also don't understand at the moment).
Good luck!