1.) I'd much prefer Magic Pockets not have an in-game explanation. It's similar to the Portals: it'd be much better if it was normal fast travel where we skip the tedious walking instead of using these magical portals that no one else seems to notice. "Oh, you conveniently found these magic pockets that there are only 4 of in existence and no one else has access to? Wow so lucky!"
2.) I don't want my MC to say things I didn't tell them to say. It'd be much better if the companions brought up a valid reason to keep the party size at X (where X is any number 1-8).
3.) Not a terrible idea, but definitely needs improvement. Given the vast amount of wealth acquirable, it doesn't make sense that companions have to find food/water. And really, setting up tents takes 16 hours per day? I suggest that, since apparently we go back to the same camp each day, we need to leave behind people to guard it. Failure to guard it means...idk, I can't think of anything that wouldn't either be trivial or too punishing.
You suggest "Failure to meet the requirements...[results in] penalties." This implies that I should be able to take all my party with me in exchange for getting these penalties.