He wouldn't believe it but I agree with kozlodoev. none of those guys is useful for serious training.
Player 1 I would fire right away (that means he could be place on TL for 1K or few thousand and fired before financial update - someone buys such players for non training spots for SC for game shape reasons), player 2 I would replace a soon as possible, player 3 is worth keeping as a rotation player for a while, but no centerpiece for training, would be nice if younger, player 4 - his salary won't hurt you, but you will let him go sooner or later and finally player 5 is solid to see some PT at NON-training position i.e. for PF if you would training at C post only (or if you would train outside players), he can't play anything else than PF/C. He could have 1-2 season left in his tank meanwhile you will be rebuilding your team. He should not receive any non team training that would be a loss of those minutes.