MOSFET selection for BLDC motor drive
Friend I have seen your schematic , I found that there is no separate switching paths for your MOSFET..since your gate resistor helps in regulating load current but it also comes in series to drain to gate capacitance which leads to slow turn off of MOSFET. Try to   keep a diode across resistor of gate which provides quick turn off,leads to less heating of MOSFET. I hope it may work.