Long time no see. I had wondered how you had been making out. There is a long history of cruising in sailing decked canoes. WanderingStar mentions two of the most famous, and a third would be Nathaniel Bishop who went from the St. Lawrence River to Cedar Key Florida in a paper decked canoe.
While historic voyaging canoes were pretty impressive, there are a whole range of modern decked canoes that are big improvememts on the originals.
If I were in your shoes I think that I would look at Chesapeake Light Craft who makes a whole range of high quality canoe designs. They also make a sailing conversion kit which includes outer hulls to make a deck canoe or kayak into a trimarran.
Kayak & Canoe Sailing Rig: Ultra-Light, Easy to Assemble and Launch!
The issue of balancing a sailing canoe under sail is not as big as you think. Most sailing canoes and kayaks use leeboards which mount on a moveable thwart. Basically, once you have the boat rigged you can experiment with the thwart position until you end up achieving reasonable balance. You can then fine tune with sail trim and leeboard rake.
My other thought that comes to mind if you plan to build a boat was a small trimarran that I designed that was intended to be constucted in a friends apartment. It was basically a simplified plywood version of the Newick Tremilino.
Tremolino trimaran sailboat for sale
The Classic Tremolino Trimaran is Reborn | Small Trimarans
My design was no where near as sophisticated as the Newick design. It used AC exterior grade plywood. The hulls rig and cross arms disassembled and could be stored in a 22 x 5 foot space. I borrowed Newick's idea of using a Hobie 18 rig and mainsail but added a bigger jib.
The main hull was essentially a very long, narrow dory with a bunch of flare. The outer hulls were loosely based on early plywood trimarran's which had triangular sections.
You might also look at Dudley Dix's Trifold 3-Fold 6 plywood trimaran