Use fake players and staff - Mixed feelings about this one as it has no real effect on your game especially at this level. An argument could be made for it in a league you already know quite well but as i'll be starting in Norway, a league i'm not overly familiar with I think there's far more to be gained from having real player pictures and the benefit of properly researched players so we'll leave it as it is
Do not use real fixtures - Keep unticked for realism
Do not add key staff - Only really of concern if you use added leagues so leave this ticked
Add players to playable teams - Again only really used for expansion leagues as leagues that come with the game will already have at least a decent compliment of players
Disable first window transfer activity - Completely up to you, could be considered more of a challenge to tick this and play with the same squads that the teams used to begin with so an argument can be made for realism
Disable player attribute masking - Must never be ticked, the very backbone of any LLaMa save. Attribute masking or fog of war as it used to be known is vital to add realism, player attributes should only be revealed through scouting/taking players on trial. No exceptions.
Prevent control of teams with manager in place - Again completely up to you, could be considered very realistic if you want to start at a team that already has a vacancy but in this case the Blue Llama has spoken so this will remain unticked
Prevent use of the in-game editor - Must always be ticked, see above with attribute masking, this is completely non-negotiable, there is no feasible reason why it would ever be used