Well, the bonus for FAI triangles is still a bonus for a free triangle, not a declared one. Moreover, in my country, flying an FAI triangle is near to impossible due to airspace restrictions.

It would indeed be fine to get a bonus for a declared task, even if not FAI.. Most decentralized competitions I know and participate in (apart from OLC) do have such a feature. Example: the French Netcoupe (http://www.netcoupe..net) has a 20% bonus for a (completed) declared task.