It's an easy idea and I didn't find a thread for this.
Forcing minimum armor means that even if someone tries to spawn naked, he will at least spawn with the cheapest armor chest and boots, which is for example Shirt with 5 Body Armor and 3 Gold Shop Price, Wrapping Boots with 3 Leg Armor and 1 Gold Shop Price.
This means that everyone should have at least one pair of chest armor and leg armor in his inventory with no difficulty requirements (possibly up to Gambeson with 21/5 Armor and Sarranid Leather Boots with 14 Leg Armor, both together do not cost more than ~ 500 Gold). This would make people stop complaining about naked people and at the same time forces people to wear equip. Depending on builds those "bad" and cheap armor also helps staying alive a bit (at least better than being naked).
The same could be done with a weapon, to force ppl spawn with at least their cheapest weapon. This would also prevent people who just respecced to spawn naked.
Not sure how this could be made though.
EDIT: Let's turn this into a "force spawning with weapon" suggestion as it is still allowed to spawn naked by rules, but having a weapon is mandatory.