You're constantly banging on about winning trophies but you're spending your first season in the top league of your country? Yes you have more users than the average country but the way you're blowing your own trumpet, I thought Mloty had changed team name..
By the way, I trained my trainee out of position last year and managed to win my top league, so it is possible.
On the topic of stamina, I train it every gameweek I have two games now and I found it's helped my team massively.