Agree that your team is good enough to win it all at level 1 but you do need to start saving some tokens and greens for level 2. Also stop all special ability training. Quality is more important

Can’t really advise you who to keep and sell as your team is really small. Minimum size is 14 and you have 16 players. So you can only sell 2 at the end of the season. The 2 I would sell at the moment are your bench MC and your starting GK.

Key positions are your AML and AMR so try to make sure they are your best and preferably youngest.