For boarding, if your upper body's a bit under strength, as you grab the gunwale or transom & get ready to hoist yourself in, several strong kicks with your fins helps a lot.
Also, make sure that you have smooth, well eased edges, all around the gunwales & transom. On some dinks, oversized PVC hose works well for this. And it doubles as a good fender
for the dink when coming alongside other vessels.
But even just taking a block plane, or wood rasp, followed by a good sanding
, to your oak guwale strips does wonders.
I had a spectacular, 9' Dory'ish dink, with a tombstone stern that I loved. And at 100kg, I could stand on her gunwales & not ship in any water.
She rowed like a dream, even in 50kts, with 5' breakers. As well as doing solo & double-handed, beach landings & launches in such conditions.
I'd snag, or build another one in a minute. Especially as she weighed all of 70lbs, & could easily carry 3 full sized adults.
The other "trick" for stability, is to attach several strap eyes, say 4-6" below the gunwales, & then run a line or cable through them. With a round, fat, cylindrical fender
in between each eye.
It adds a good bit to your stability when you need it most, regardless of the type of hard dink. Just make sure that the line or cable is snugged up Tight, in order to get the most benefits from the fenders buoyancy.
Also, when you find/get on that you like, Do Three Things:
her ugly, & make her look scruffy, so she's less attractive to "sticky fingers".
- Fit her with a cable so that you can lock her up, including to the mother ship. And drill holes through the blades of the oars, big enough to slip the end of the cable through, when locking her up ashore/to dinghy
- Take a set of lines/measurements off of her, so that you can build another, whenever the need or desire arises. For yourself, or a friend.
*** As I surely wish I'd have done so with that little dory of mine! ***