I don't think that being unable to fire through trees is broken. It is broken when you can stand units inside single trees to make them untargetable from all angles. So this fix sounds good and I don't think you need anything extra.

It would be nice if we could make units shoot at trees to clear them without having them waste their time trying to shoot through wreckages. But we should be able to make do without.

Yeah I forgot startboxes, needs another update anyways for minimap