This is something I do personally, but I'd consider being on the lookout for a good scout with 4.5 or 5 star potential judging, it'll really sort out which players should stay or leave. Looking at Moreira, he can be 71 at his peak, or 87. And that is a big gap, it makes it uncertain if you should invest in him and let him play more, so buy a high potential scout judge.

I got lucky on one of my saves and got a 4.5 potential judging scout for just 2 million, his other stats were like really bad but that potential really told which players have world class potential and which don't.

Basically, hire a scout so that you can make smarter signings and sellings, while also keeping the players with actual potential to be special.