Now here is a coincidence. I have been mulling over something very similar this week.
Making buildings and jetties for lakeside scenes could be a side project for club members. Something to do for a change of pace, if you are waiting for parts or just fancy a change. Ideal for those club lakes with a concrete bank.
If clubs agree on a particular scale, the whole diorama scene can be extended over time, as any individual can add a new building. It will not matter that a lot of boats are different scales, as long as the buildings work together. It is something that younger modelers can also get into. Maybe parents could pre-cut and kids can assemble. With a bit of extra design for pins or hinges, these buildings could even be flat-packed. That way members can easily bring both their model boat and building in the car together. At the end of the day, all can be taken home, and so hopefully no problems with the local council.
Not only will it make the waterside to the next level of modelling, it would also generate more interest from spectators, and may even attract a different type of modeller to the club. Maybe some Tamiya trucks or even tankies.
Just thinking at a tangent again.