HI Lauriem,
I was speaking with one of my colleagues on Sunday and mentioned your problem. He said not to use the false keel because in the speed boats I mentioned, the longitudenal centre of roll is low to start with, and the keel would help more to reduce sideways drift when turning a buoy.
Whilst rudder off vertical would tend to contribute towards the dig in and potential roll, he asked about how high the motors and other fittings have been mounted and if possible to get them as low as possible. 💭 , being so lightweight being plastic in the main (I presumed its plastic) a tendency to roll would be more likely than a weightier moulded fibreglass hull. Sorry this is out of my knowledge range but I hope these comments might help.
You mention your Perkasa. I have been offered a full kit (45" is it, the bigger one anyway) second hand at a very reasonable offer price. is this a good and straightforward kit to build. is it "plank on frame" or "plate on frame" (I imagine plank because of the way the bows curl under). Furthermore, what engines would you recommend for such a beast and would they need water-cooling. I imagine that induction motors would be recommended because of their power but I have got to ease up on my spending.

Yes I guess that it might have been a bit difficult. Never mind, it is good to chat with you through this website if that is all we have available at present (barring Star Trek Transporters!!!).
😯 👋

nice looking boat,hopefully mine looks this good when finished