Mr. Force, you have been given a lot of good information here, and I do not disagree with any of it, but let me give you just a slightly different perspective. I owned a 42 foot Grand banks going all over the place at an easy 8-knot cruise for a lot of years burning an average 3.25 gallons per hour on two Lehman 120 engines. I rarely used the flybridge underway. It turns out that unless you have a very light colored bimini, I gets HOT up there in summer sun as the heat a dark cover collects radiates right down onto your noggin, especially when you stand up. Getting up and down from there was not especially convenient either on that boat, and NOBODY was allowed up there or even outside the skin of the ship at night during coastal passages. Hey, and the refrigerator with all of its delicacies was below right next to the lower helm.
A flying bridge adds cost as well as maintenance issues.
Sooo, when I got tired of 8 knots and all the maintenance of a big boat kept in a wet slip and wanted a diesel boat I could spend the night on at anchor in air conditioned comfort, a marine surveyor I know said I needed this Mainship 30 Pilot II Rum Runner. They come with and without the hardtop and with or without the generator installation.
A few specs to consider: Yanmar diesel 315 six-cylinder or 240 four-cylinder engine
Boat weight 11K pounds for soft top, 12K for hardtop
Fuel 150 gallons; water 40 gal
Genny: 3.5KW Nextgen
Hull speed, something you should learn about, is about 8 MPH (3-plus gallons per hour fuel use), and the boat will rapidly climb the hill thereafter until about 14 MPH where is drops the bow through, but not dramatically because it is a semi-planing hull. Any speed in between has the nose in the air with reduced visibility ahead and hard use of the engine trying to climb. My personal preference is to run the at around 15 MPH at 8.4 gallons per hour per my Floscan where the engine is at about 80% power (diesels, especially turbo-powered ones like mine) like this.
While it is out of the length of boat range you specified, the Mainship 34 Pilot has a hull speed about one MPH higher and can be had with twin engines.