FWIW (I'm late to the party -- don't usually monitor this forum) --
The FT-857 and IC-706 are very good choices -- all bands, all modes, very compact, separable head. I believe the FT-857 is the cheaper of the two, now. You will want a narrow IF filter if you do serious CW work.
You might try using a coax-fed dipole. Tie the lower end to the stern pulpit, and hoist the upper end toward the mast. It'll be a "not-quite-vertical" dipole, with good low-angle radiation (if you're over salt water).
There has been considerable discusson of the setup in the Seven Seas Cruising Assn "Communications" forum, with Bill Trayfors as its leading advocate:www.ssca.org
[click on "discussion forum"]
I've used one for testing on my 36' sailboat, and it works well. Bill has some construction techniques that make it last a long time in the marine environment.
For regular HF use, I insulated my backstay. Stay-Lock insulators have a pretty good reputation, unlike many swaged insulators; they're expensive. My counterpoise is several wires (of different lengths) running from the tuner (in the aft cabin, at the base of the backstay), forward along the toerails, to the bow. That's not supposed to
be enough ground plane, but it's worked OK for me with an SG-230 autotuner.
I use my VHF masthead antenna for 2m work. I haven't measured the SWR, and operate my IC-706 at half power on VHF. You'll hit _all_ the repeaters, way out.
If you haven't been warned about high noise levels in marinas, I'll do it now. Expect S8 - S9 noise from battery chargers and inverters on surrounding boats. If you want to work SSB, leave the dock. You may be able to work CW and digital modes through the noise.
Charles ("Right Galah", 36' Morgan Out Island)