Great list, but I do have some thoughts:
Loan players should be inelligable when playing against parent clubs
That's not a general rule though (remember Courtois vs. Chelsea in the CL last year).
Ability to join the game at a certain point to try and turn a situation around EG, join the game with 300k Fifa coins to go with the scenario already set in a similar way to the ones used for World Cup DLC etc.
I remember this used to be a thing in older FIFA's, I think around '04 you could sim and then intervene and play out the match.
Option to change kit sponsor for a yearly fee (obviously might bring up complications with current sponsorship deals and licensing etc)
This will never happen.
Ability to appeal a straight red card decision
Sort of silly since the game functions under the presumption that the referee is always right. I remember a Champions League game from about 10 years ago where the referee had a small random chance of making wrong calls (e.g. calling offside when it's not) and that was one of the most frustrating things you could ever deal with in a football game.
Ability to customise the appearance of your manager character. Perhaps even with a game face.
I personally think this is way too much work for an NPC that you'll only ever see the back of the head of.
Option to start Unemployed and for jobs to become available depending on manager performance. Ability to apply for jobs and have an interview process and manager reputation dictates what teams approach you.
I think starting unemployed could really make the game annoying in the beginning, I mean, if it's not about playing football you might as well play Football Manager.
Ability to be subbed off due to poor performance
Pretty sure this has already happened to me?
Ability to start on the bench and be subbed on.
This would be OK if it worked like intervening in a simmed match. If not I don't think I'd be interested in watching 10 minutes of simulated football to play the last 2 minutes (plus this usually guarantees a shit rating).
Also, I generally don't think you should hit people over the head with a whole bunch of new features. This isn't Football Manager or a Bioware RPG. Most people, I believe, play CM to add some context to their playing (as opposed to constantly playing friendlies). EA should try to add as many features of this list as they can without making them a burden to players.