A couple of points (just my thoughts) Rather than an 8:1 mainsheet I'd go with 6:1, but with a short fine tune as well.. that could be 4:1 and give you lots of power for the last few inches of trim. 8:1 is going to mean an awful lot of line to pull through all the time, and it will be slow when the loads are light.
You appear to be planning stoppers/clutches for the pole down/lift... I think they are a bit too awkward to use readily and often, fairleads and camcleats can be arranged to be easily released and re cleated even from several feet away in the cockpit. I'm not at all sure that you'll need a winch... if you double your downhaul at the foredeck you should be fine on a 34 footer - just don't let it get away on you.
You may find the mainsheet hanging in the companionway a bit of a pain and often out of reach.. but you've not got a lot of room left to run it forward and back like it probably is now. It's rare but I've seen mainsheets run aft along the boom with a cleat on the boom more or less overhead in the cockpit. Problem then is access when the boom is outboard going downwind - you'd need a pretty long tail.
Anyhow, good luck and hope it all works out for you.. that's a fair bit of hardware you're planning to buy!
1984 Fast/Nicholson 345 "FastForward"
".. there is much you could do at sea with common sense.. and very little you could do without it.."
Capt G E Ericson (from "The Cruel Sea" by Nicholas Monsarrat)