Re: Boat unstable on plane
To add to my last post. Several years ago I had a 14 or 15 foot fiberglass starcraft with a 35 hp rude, with the engine attached I could lift the stern and reposition it on the trailer, it was that lite.
I took it out on the pacific and found out in short order that the sea was in control no mater what size the swells were. Technically, I did not make a big enough footprint in the water due to the lack of weight. Two more people on the boat made a Lot of difference.
So in answer to your question, this is fairly normal for your boat size and weight and as you have noted above you have learned how to deal with it.
I suggest that you add a few guys (about 450 + pounds and see how it reacts to the same size swells. You will be surprised.
On the good size, being a lite boat you will save on fuel
My 2 cents
Hang around this place will grow on you
Be Well