"My current method is going through the Player Search list and sending /tell's to anyone that's not in a free company, asking if they would like to join. I dont send random invites, and I dont spam them with /tell's, and i avoid shouting as I know all of this is frowned upon."

this is what I do weekly and I'm running a 80 man FC by now D:

some differences between us there might be:
1. My FC prides itself on hosting Tuesday Casual mini game nights, Thursday old content clearing nights and Sunday movie or different game nights. We also once in a while host global events like glamour competitions. In other words we're doing all we can to stand out.
2. I'm on Odin. Very high pop. Low pop recruiting will always be so much harder.