yes but you also have to remember that marin is still relatively young. There is a lot of time left for him to do big things
No, first thing he is head-case and if you are that you will be that whole career and you will not do anything. Second thing, you can't be young all your career. Why Djokovic isn't young than, or Murray, Del Potro? This is his 5th season that he is regular on tour, he has played almost 350 matches, won over 200.
It left just 4 more years (maybe more) for him and his maximum will be to be weeks in top 10 and that's is. Only reason: so fucked up head. He is away to sensibile, that's his problem.
But you never know, maybe something will switch.