There’s a whole topic of course:
I favor series Schottkys, which protect against power reversal but do not help in case of shorts and do drop a little voltage. But only a little, you shouldn’t be relying on your power rails for precise voltage values anyway, and pretty much the only time you possibly have a short is when you power up the module for the first time, and before doing that you should be testing for shorts. And series Schottkys can be easily fitted to existing PCBs in place of 10R resistors or (twitch, twitch) ferrite beads.
A matter of taste, though. Polyswitch fuses are cheap enough and if you have the PCB real estate they’re good insurance.