No doubt Trossard is a good player, and sometimes he wins a game for Arsenal, but I disagree with you that Trossard is a better player than Martinelli at Arsenal because Martinelli is one of Arsenal's players that used to force attacks for Arsenal, and anytime Martinelli is not fit to play for Arsenal, Arsenal always struggles to win a game.
I agree. Martinelli is better, I still think they need better than both 
. But, if we are comparing only Martinelli and Trossard then I would say Martinelli is better. Trossard also has some great offers from other clubs who see that he wants first team play, constantly and not want to be bench, so if he wants to then he can leave anytime he wants and get first team play anywhere.The only downside right now is the fact that if he does, then he will seen as he ran away from a competition to get the starting spot, and that will not be good for his value on the long term but he is aging so I doubt he would care about that at the moment. What he should be caring after this age is trying to get as much money as possible. If Arsenal wins a title without him, he will never hear the end of the jokes though lol.