The channel that made this video has a few really good tests like this for XT60 XT90 and some other connectors, this can give a decent idea of the kind of current these connectors handle over a given period of time.
That said: if you’re asking whether or not to worry about the XT60 on the VESC, I wouldn’t worry about it.
The power button itself is just a power button, it receives power and sends a signal to the VESC which (in the case of the DV4S) has a built in anti spark circuit.
The purpose of anti spark is to turn on/off power to your ESC without the spark that happens when plugging it in,
Some are built into the speed control (like yours) and only need a button to be plugged in to use.
Some are a completely external module like this:
And some use an XT90S connector and make a loopkey like this: How to make an XT90 Loop Key
Your DV4S can just use the power button to cycle on and off.
Also I missed this prior but:
Soldering sensor wires is definitely possible but it takes quite a bit of finesse and can be pretty frustrating in my experience.
I generally crimp my sensor connectors and will only solder them if they cause persistent problems.
Here’s a guide on crimping jst connectors
