In my opinion, bomb rush got a little bit boring since it has been introduced. My main issue with this gamemode is that it lasts much longer than the other fun rounds. I would suggest that when the bomb timer reaches zero, the bomb explodes the person holding it, but also damages players around it, like a c4. This will create chaos and the fun round will be shorter. Sort of like harpoon wars. Everybody loves that fun round. It is short, simple and chaotic.
As of late, I've seen bomb rush be popular on the servers and it only becomes boring for a majority two/three times in a row which is true for any fun round. I agree that damaging nearby players would be a good change, but I don't think that it's a necessary one.
I would not change the game's basic mechanics and therefor not add area-damage. Instead it might be beneficial to increase the concurrent bomb count.
I would just increase the number of bombs on the field, it'd make things much more interesting, chaotic, and faster.
Alternatively make another fun round called rush bomb where everyody except for one player has a bomb, everybodys timer resets when someone passes a bomb and the person without one has to go 20 seconds without getting passed to
I'd rather go with the idea to add more bombs on the field, as it technically does fulfill my wish for the game mode to be shorter and more chaotic.
-1 I made a moderator rage quit on this game mode and I always place second sooooooooooo good gamemode