Where ever applicable and able. Swap out screws which seem to loosen more with either:
1. Thru bolting with washers and nylock nuts or
2. Longer screws with elastomeric or "powder" or plastic shreds left over from drilling and installs
3. Use longer and fatter screws with the above mentioned thread lock aids.
I had screw problems, just decided to not have them anymore.
good luck, Molar