None of what you suggest "fixes" any "problem".
Militia being dumb is series tradition, and while they could stand to be a bit smarter, the same can be said about the enemy and they more than adequately provide the most vital service they exist for: defend sectors in auto-resolve.
Mines running out is intended to stop you from camping a single one forever as you train up all your mercenaries to 90+ in all stats, it does exactly what it should in exactly the way that is necessary.
The inventory is hardly restrictive if you have even ONE strength based character which while unfortunate is how they decided to make that attribute valuable to have.
Even on this you are merely swapping one problem for another, and Strength is a bad enough attribute as it is.
Dropping tons of gear you cannot use over some gear that may hold value is stupid, almost no game does this, because it's pointless busywork clicking away through all the trash instead of being excited about the one good item you might get. This is ultimately an RPG, and one where you won't find a "Rifle +1", so you may well not drown in a sea of garbage.
The economy is nowhere near stringent enough for this to be necessary either.