Militaristic CSes have obtained big boosts compared with vanilla. Firstly there's the UU (in my current game I'm far too early to enjoy the benefits of Sidon's Panzers, but as I'm playing Siam my own UU will eventually upgrade to them - just a shame the useful life of tanks is so short in G&K). Less well-documented:
1. There's a lot more consistency in which units they'll give you. In my experience they'll reliably give you the most advanced land unit you have the tech to build - Sidon gave me a chariot archer pretty much as soon as I'd researched the Wheel, and I was receiving regular pikes, muskets and rifles from Budapest in my last game. No more Archers helpfully being granted when everyone else is using Artillery.
2. The units now spawn in the territory of one of your cities rather than in the CS' own territory, so they don't need to be walked all the way home (haven't used Patronage since G&K yet - though will in my current game - but I presume the long GE trek home is also over. I hope so anyway).