My SOF has 17 degree gunnels. It's 18', 19 3/4" wide. It's fast, good secondary, not -so good primary and an easy roller but not like the super low rolling machines that are commonly built now.

some basics -
The flatter th bottom, the greater the primary - the slower it is.

A more "V" hull bottom is faster but less primary.

The greater the chine angle ·angled up from the chine to the gunnel - the greater the secondary stability. but the more angled gunnel will force your ribs inward creating a narrower bottom - less stability.

A shorter boat will be easier to roll but slower.

A longer boat is faster relatively and more water resistance to roll.

Unfortunately all boat building is trying to best use all the compromizes to achieve the closest thing you can come to for your desires.

My SOF tetters on the bottom which is slightly annoying. It has good secondary however. I may build another this winter. I will keep the 17 degree gunnel angle. I will decrease the length to about 17'4". I will flatten the bottom a bit. And I will lower the volume overall. You can flatten your bottom by making your chine stringers a little taller than the keel so you create a flatter bottom and not rely totally on the rib bending shape to achieve that.

The one decieving thing about SOF's is how much space gets eaten up with the ribs and interior wood structure. A normal low volume boat is really so much tighter to squeeze into as a skin on frame, especially if your tall. the same kayak made of plywood would have room to spare! Good luck - Wit h SOF's its always a bit of a experiment how it will end up feeling .In many ways that the fun of it expecially since it's the easiest of the building methods. You second one will be done without even thinking.