As already pointed out by someone else, there absolutely needs to be a maximum (4 or whatever) number of mechs that a person can take, so you can't do it purely on tonnage. There are tons of players who can use a single jenner or firestarter to kill multiple mechs above their weight. Those players could simply stuff their dropship full with around 7 or 8 light mechs if there wasn't a limit on how many mechs you could bring.
If you weren't forced to bring 1/1/1/1 we already know what the answer would be from our current weight class percentages in the queue; very few people would bring light mechs. This changes the balance of the game. Generally speaking, outside of light mechs, the heavier of two mechs is favored to win in a fight. I.e. a victor can generally do the same thing a shadowhawk can do but better, and please, no anecdotal evidence about that one time your medium mech killed three assault mechs.
Medium mechs need light mechs to be their prey. Even here light mechs stand a good chance vs medium mechs, but at least medium mechs are suitable for fighting lights because of how prominent missile slots (i.e. streaks) are on medium mechs and how they're agile enough to keep up with them compared to a dire wolf who's in trouble if caught alone by a light mech.
Light mechs benefit from having enemy light mechs to chase off from their teammates in order to reach their full potential.
If you don't use 1/1/1/1 you'll just see a game full of mostly heavies and assaults, which is not what MW is about. Even if you limit someone to two of each weight class then you'll likely just see twice as many heavies and assaults compared to mediums and lights. Having a mix of all the weight classes is important for the food chain and the general feel of the game.
1/1/1/1 with tonnage limits is the way to go. If you don't like a certain weight class it's your problem. Not everyone can be the star center on a team, someone has to play goalie, like it or not.
Edited by oneproduct, 26 September 2014 - 04:30 AM.