The solutions to all of strategus' problems have already been solved in the single player version of the game.
First, What are the problems with strategus?
1. 99% of players are delegated to boring "crafting" system
2. Massive alliances
Fixes for said problems?
1. Limit troop count that one player can have at a time to ~100 troops. (Much like in single player, charisma and leadership skills kept your maximum army size at ~100-300)
What this means? Large groups of players would have to follow each other in order to make a large army. 10 players following each other would be able to reinforce each other for a total of ~1000, 20 for 2000, etc etc. This means that if an ally wants to help you, they can't just shovel their troops/gear/gold off to an ally, they have to support with actual players on the map, leaving their own villages defenseless.
This would be an easy fix for one of the largest problems in strategus.