Does scouting or game planning for the midweek sim change anything? In other words, does it matter if we do the game planning in midweek or game day sim?

I am assuming the answer is no and the mid week is just for signing/releasing players.

In the same vein, are midweeks really necessary? In MFN-2, we are 3 games in and I am the only one to use the midweek. Just something to look at as the seasons of different leagues progress.

You are correct, it doesn't matter whether you game plan before or after the midweek, the midweek just gives you an opportunity to sign players between games.

I'm toying around with the idea of having some leagues sim more quickly - probably every 12 hours instead of every 24 kind of a thing - but I don't think I'll remove midweeks altogether because if you have some injury issues you could get into a bind since there would be no way to sign players and then place them into your depth chart without a midweek sim.

No problems about keeping a midweek. I will say I really like the daily sims. I think that is perfect timing.