User blog comment:RayShepp654/How to defeat the Reapers Theories/@comment-2130363-20101025161944/@comment-2174252-20101026151749

All good points. However, although the Tranix cannon is the most powerful weapon, that we know of, in the galaxy, as you well said, it took two shots to destroy the Collector ship which is only a cruiser. A reaper is ten times bigger and has better shields. It will take a more powerful weapon to bring it down quickly.

I agree on the whole ”uniting the galactic community in a common cause”  thing. Shepard has been doing that since the first game if he/she followed the Paragon path: saving the Rachni queen, saving the Council, reprogramming the heretic Geth, etc. I believe he/she will have more opportunities to unite the races in ME3.