Tom, these are the finished lengths and materials I used for the various lines.
Main halyard: 3/16 Technora core, 5/16 Dacron cover, 100 ft total - 45 ft uncovered, 55 ft covered, 10 ft overlap. Technora because it is strongest.
Jib halyards: 3/16 Vectran core, 5/16 Dacron cover, 90 ft total - 40 ft uncovered, 50 ft covered, 10 ft overlap. Vectan because it is lighter than Technora but no stretch.
Spinnaker halyards: 3/16 Spectra core, 5/16 Dacron cover, 96 ft total - 38 ft uncovered, 20 ft covered, 38 ft uncovered, 20 ft overlap. Spectra strong enough and lightest. Cover in middle so ends can be swapped if one end gets worn.
Topping lift: 3/16 Spectra core, 5/16 Dacron cover, 60 ft total - 36 ft uncovered, 24 ft covered, 14 ft overlap.
I use "luggage tag" splices so I can replace shackles without shortening halyards. I use halyard stop balls so the splice doesn't get sucked in to the sheave box and stuck.
I use reeving splices on the cockpit end of lines and replace the high-tech halyards with 1/8 dacron pull lines when the boat isn't in use. This avoids UV related problems and only takes a few minutes once you get used to it.
