1. What size mainsail halyard are you guys using? I currently have a 6mm halyard but find it hard to get the sail to hook on, and if it does hook on, I find it hard to get it down after that.
4mm plain dyneema. Works well and doesn't seem to wear down any parts. It may feel thin when the sail is very hard to raise up the mast, but that probably means you have to clean out the sail track or clean/smooth the luff rope anyway.
I'm not think about changing this halyard for a thicker one, Have been using this exact halyard ever since 2004. It chaffed on me only once at the very end.
2. What do you do to make it easier to snuff the spinnaker? I find that my spinnaker bunches at the opening of the chute and it gets pretty hard from there on to snuff it into the spin sock.
-1- good technique (quick full pulls in the beginning)
-2- a small spacer line between the top patch and the others about 200-300 mm long.
-3- Some also use a lubicant but I never have.
Best of luck.
Wouter