Both of these have been brought up in the past.
To begin with clans have been brought up before. This got a positive response, however I don't think a full suggestion has ever been put forward that has made it to the popular suggestions forum.
Item trading, however, had a negative response. While it seems like a good idea, with the current mechanics of the game a player is unable to buy parts to a mech a lower level than there current level. Adding trading would encourage players to create a second account to then trade all there good parts over to the main account when they reach the level they want the parts for.
It could also add a big unbalance to the game (like many other games that have introduced a trading system) where the top players that get the legendary items and don't need them will sell them off for a huuuuge profit. They can then use the money they have made from selling one item to buy many more item boxes and repeat untill they get the items they need to dominate.
This is only two examples of the problems of a trading system that come to mind from previous topics. However with the changes they are possibly making to the game, there may be a possibility to implement this idea. As the game stands right now though, the response has been no so far.