You may have some trouble finding something with proper seating in that size range, especially in a nesting dink. Though it'd be possible to rig up some detachable fore & aft soft seating. Like say, some mini longitudinal hammocks? They'd probably take a bit of experimenting to get right, but would keep your backside off of the wet hull
There's no shortage of designs, but some of the popular ones are;
Danny Greene's Chameleon
Dave Gerr's Nester
Russell Brown/Paul Bieker's PT11 & PT Spear
Paul Butler also has a whole bunch of designs
Otherwise try the WEST System sites. Both the primary site, & their quarterly Periodical via the sister site. As well as the Wooden Boat Forums
, & of course, online searches.
Given a small amount of study it becomes pretty easy to discern how a design will perform via each method of propulsion
, as well as when it's heavily loaded. So it's worth gaining a discerning eye prior to investing a couple of hundred hours in a build.
For my money
, I'd do something like the PT11 or a modified Dory design. Especially as they're both fairly light boats, & are easily propelled via any means.
Russell Brown has outsailed a LOT of boats in the PT11, of all sizes & configurations, including a number of multihulls. And they've got such choice lines.