Even with the game unmodded there is a huge place for bomber, you only have to keep in mind that bomber is not a lone wolf role (as happens with most of the other roles), I'm very proud to be a member of the
Escuadron 69 becasuse we have so many people, along with the comradeship and our special sense of humor, that we can specialised in our favorite role, in my case it happens to be bomber.
There is many ways to do things with the unmodded game, while playing offline can be tedious because of the IA and its waypoint way of life, coop its where transport mission can be better done... but i think the limit for this simulator is where the mission builders set it. I flew a few offline campaing that you need to land on certain places so you can pass the mission, and now with the triggers mod thing for the mission builders we are going to see a new revive in Il2.