Ok so Raven is a bit bigger than 18 but.....our reefing lines are mainly outside the boom as is the outhaul. All four lines (three reefs plus outhaul) go into the end of the boom but them exit a way along. We have one winch on the boom with ordinary cleats that will soon be replaced by jammers. That's the only part of the system I insist on changing. Not state of the art but it works.
A further improvement would be to have the winch on deck but I'm sure that's irrelevent for you. The advantage of course is that on deck you have a more stable winching platform than a boom provides.
"Do you think God gets stoned? I think so... Look at the platypus." Robin Williams.