Even though i trained almost all my players at free throws at a high level, shouldn't the free throws level up just by Jump shoot training???
No. This has been a debate for a long time because people say it is not realistic that they would be such good shooters from the outside and then suck at free throws, but in the NBS and other top leagues, players practice free throws every day and every week. If you want your players to have better free throw shooting, feel free to train it! FT pops fairly quickly, but people don't value it enough to train it as much as JS training and other skills, which is why they are typically lower and people complain.
And does the pace of the game (from the game strategies) affect how fast a player is getting tired??
In transfer market i can see amazing skilled players that have terrible stamina, how can those players play almost whole games???
isnt that a risk to their health???
Yes, pace of game does effect how much your players get tired, so slow offenses tend to allow your better players stay in the game for longer, but that may or may not always be beneficial. Players that have amazing skills will still be amazing while they play regardless of low stamina, however if they are playing 40+ minutes, towards the end of the game, they will not be nearly as effective as if they had higher stamina. More minutes means more chances for injury, but it isn't really a huge fear, nor should it be.
Am i being helped by the high stamina of my players or shouldnt i train their stamina like almost everyone else is doing?
I don't think your players need more than 5-7 STM personally but you definitely do not want all your players at 8+ STM or something, because than minute distribution is difficult in my opinion.
Murray/Harris/MPJ/Grant/Jokic - 2020 NBA Champs