I've been looking over the map very carefully every turn on my HRE campaign, and I feel very strongly that the ideas for having every player participate more actively in direct provincial controls would be very easy and satisfying for everybody.

I've seen some people overcomplicate this by bringing up save games being passed around. This is unnecessary. In order for multiple players to play one faction each with a seperate garrison or army or whatnot, all you need is the following.

1 - Players to keep track of the location of their own units.

2 - Players to send the necessary movement requests to whoever is the emperor by a certain time. The emperor will handle all of the actual movements, but cannot move armies (except his own and the imperial army) without the order being given by the controlling duke.

Example - The duke of Innsbruck wants his army moved south to block Venician armies from using the pass. So he would send the emperor a message telling him this. The emperor could then carry out this movement.

3 - Players to understand that giving up units to the Imperial Army or a Crusade means they no longer own this unit. The duke of Innsbruck may own 6 spear militias, 2 peasant archers and 3 mounted sargeants, but if he gives up 2 mounted sargeants and 1 spear militia during a Call to Arms by the Emperor, he can no longer give orders to those relinquished units and they become the property of the Imperial Army, therefore whoever the elected emperor is at that time. This then leaves the duke of Innsbruck with 5 militias, 2 archers and 1 mounted sargeant, he would have to petition during the next edict session to have more troops recruited at Innsbruck.

This brings about another idea. Players who conquer territory through the use of their own Ducal army become Duke of both territories, whereas territory conquered by the Imperial army becomes a general part of the HRE and can be claimed by new players as their duchy or remains a part of the territory under direct control of the elected emperor's authority. Players with more than one duchy may opt to give up some of their posessions to new players to have that player join their ducal house (like the family ties of Rome. This is very possible, as M2 allows generals who are not actually tied to royal family. I.E, generals exist in the campaign that do not appear in the family tree, allowing the roleplay of alternate family ties to be a very feasible possibility).