So far as I'm aware, the MKS controller should run on 24V just fine.
The screen should be running off of an on-board regulated 5V, so supply voltage isn't an issue there.
12V fans get kind of excited on 24V and won't last long. Not recommnended. My MakerBot clone uses a 12V part cooling fan with a resistor to allow it to accept 24V input. You have that option for your fans, too, if you want to check your fan's DC resistance, and can match it with a high wattage resistor. Probably cheaper than 24V fans, but not always so easy to replace.
The heated bed, and cartridge heater for the hot end should be changed to 24V versions. You may also need to adjust your stepper drivers for current to keep your motors from burning out, depending on what drivers they are. The higher voltage should be good though. our motors will be more responsive, and faster.
MBot3D Printer
MakerBot clone Kit from Amazon
Added heated bed.
Leadscrew self-built printer (in progress)
Duet Wifi, Precision Piezo parts