I use both Jack's site
http://dominions.realites.org/
and ballbarians tool occasionally to spice up my SP games. I generally use Jack's site and jack it up to 50% + starting provinces. So random commanders, buildings, and items sprinkled about the map...some so dangerous that they're still indy after 6 years of gameplay
I also love having the starting province be randomized, so the AI and myself get a free commander, maybe some low level items, and a few extra troops. It can occasionally prove messy when one AI gets a really good pull and beats everyone else up...but that's the fun of it
I agree the game needs:
disband
some form of diplomacy
Hold and Fire command
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