I think this is a common problem...
i have taken off all the white plastic on the rigging except where sheets rub against the shrouds, and then I have replaced the original stuff with a size larger, so it turns as the sheet moves past it...Plastimo have a lot of different sizes available.
As for the corrosion at the swage ends, i have two products..one is INOX which the previous owner swore by and left on board, and the other is a NZ product called GRUNT.
They both work in a similar fashion. Paint it on, leave for about 15 minutes and then hose off with fresh water.
Result : rusty marks all gone
Grunt works well on gel coat too...for rusty marks..e.g. on deck at the bow where the anchor chain comes up.