@Animalz – I think you should use flitch beams in the rafters of the gazebo. I renovate “fixer upper” houses with a friend of mine on the weekends, and use flitch beams in all of the roof renovations. I use a lot of them in roof truss construction because they’re so much stronger than simple wood beams.
It’s not the normal way to do things, because it’s so time consuming, but when I build a new truss for a project, I use flitch beams for every part of the truss. I replace broken or warped rafters with flitch beams, too.
When my friend and I show off one of our finished houses, we always stress how the flitch beams make the roof sturdier. The buyers are usually happy about that. It seems like they’re willing to pay more money because they feel that the house is strong.