It is not easy to get myphical you want, after all, its myphical and not yet another common/rare. No wonder why so many people like idea of "trading" - they want to get myphicals they want but don't want to do daily missions for half a year or grind campaing for chance to get myphical from standart box.
what is easy to forget is that if something valuable is easy to get, it suddenly becomes much less valuable
With trading, once you got enough myphicals and other valuables you can trade them for whatever you need and build mech of your dreams... except, when you build it, you realize you now have no dream to follow. You could want to make any other mech you would want, its just matter of trading for other myphicals. And even making more mechs for 2v2 or 3v3 is just matter of how many required myphicals you can get via trade... Now, if you are not noob, you reached the highest height you could ever reach...
...the questiion surfaces: if you reached everything you could reach in this game, why you are still playing? And if you realize you have nothing to achieve in this game, you will go look for something else. After all, here you are already winner, so why keep playing the game you already finished - if you can go and try to conquer other heights?
Thats why I vote against trading in any forms. If every player is ever able to get items they just needs, game will be just matter of pre-made powerful buildsm with everyone being on the top - thus, no struggle to get stronger, no real competition, nothing to keep most players. 95% of players will quit playing in 6 months or less. Not to mention, no one will ever buy damn tokens