Ok, yes, I’m no good at electrics . . .
I'm no good at interpersonal communication but I don't let that stop me. Sometimes it can be shocking, just like electrics. You've already replaced the bulb so you know if you would have room to stuff an extra socket and wiring in the shell. If you can, get the H4 option without the posilocks. At the end of the day, installing a relay helps lengthen the life of the switch. How much it lengthens that life is anybody's guess. It also allows bulbs to burn brighter because it reduces electrical resistance. That also means bulbs will burn out
slightly sooner.
I'm not constrained by the lack of a relay. I see as much as I need to see with what I've got. Furthermore, I have no desire to dazzle drivers and animals into a confused stop in the roadway in front of me by using high power lights nor do I have a desire to blaze a pathway ahead of me tempting nearsighted animals in rut into using it to cross in front of me. I use a 60/55 halogen bulb. I replace the six dollar bulb every two years. I haven't had a bulb burn out after thousands of miles of pothole riding, but I always have spare bulbs with me and changing a headlight bulb on my moto takes the removal of one Phillips head screw. I ride at night on highways and back roads. I enjoy it.
Maybe I'll install a relay before my light switch fails me on a mountain road bend but right now, I'm on a highway to Hell.