So basically you have 2 key players, the ST and AMR. You really have a good team, no 7's in the ratings and thats a rare case.
Then, these 2 players probably are alternating to resolve the scenarios, playing at high level and if one doesnt resolve the scenario the other one will work on it. Then it can happen that if both players have a expected synchronized drop on rating or performance you wmay need to focuss on others or even sub one of them to achieve the goal.
About the GK with all these 8's... you need to check out at the performance vs equal or higher teams, to know if he's worth, so if there is any mistake on defence you need to focuss first of all on your GK if you want a replacement.