What value capacitors did you use for protection? Usually you'd pick a value that would be considered very low for a crossover point but would be sufficiently out of band in normal operation while still offering DC protection. Also helps if there's a mis-patch or wrong processor setting used, the idea is hopefully someone would notice it's wrong before running the rig all the way up.
As has been stated, finding the "right" value for a fuse is usually trial and error.
Using a light bulb... that's a compromise too and if you are having sound quality issues with capacitors I think using a bulb is going down a similar path. That said, if I was to try a bulb the 1156 recommended by Richard would be my starting place for 50 watt drivers.
Bypassing the cap with a fuse is a good idea but one possible downside is you might not know the fuse is blown unless you inspect every fuse in the array. Yes the drivers continue to operate but with different response curves.
As always in audio...everything is a compromise.