Laser,
I ran into the same issue being 6'4". The only boats that I found to have sufficient headroom was the Lagoon 380 and 410's, the new 42 Manta's, (The Headroom was increased in 2005), Voyage 430/440, and the 38' Admiral yacht. We ended up with the Voyage 430. We wanted to go with the Lagoon but wasn't satisfied with the lack of galley space. I am sure there are others that we never got to. We also checked out the Island spirit's, older Manta's, and some of the older Fountaine Pajot's and found they all lacked sufficient headroom in the salon. Though most of them did have plenty of headroom in the hulls.
As you know everything is trade offs. For us the must's were headroom, galley up, external engine access, and Yanmar's. If you have any other questions, let me know. Good luck on your search.
Dave
tilmonday@juno.com