Why don't you add damage phases to all bosses so they only take damage for a limited time. For example, you damage a boss until a quarter of its health is gone. Adds then spawn and until the adds are killed you are unable to deal further damage to the boss. Once the adds are killed you can then damage the boss again until it's at half health then repeat. This would solve the problem of destroying atheon in 17 secs. You can add in more majors, add more non solar shielded majors etc. There are ways around it. You panic and start nerfing instead of looking at other ways. The above was just an example and I'm sure there could be some other ideas people could come up with; that would allow weapons to be brought forward.