I tried UFO, but the was an issue where I was unable to hire some followers. It seems development of UFO has ceased, so I dropped it.

I tried SMF by Kurtee, but it automatically reverts followers to their default armor when they are dismissed (by design). That's unacceptable, as I want to equip my housecarls and steward with custom, better armor, and want them to keep it equipped even after they are dismissed.

What are some good follower overhauls, and what are their features?

AFT, Advanced follower tweaks is hands down the best one.

I use AFT in my games too, and I'm very happy with it. Here's a link, if you want to read more about it: http://www.nexusmods.com/skyrim/mods/15524/?

AFT looks good. I'll give it a whirl.

One question:
(From the description on Nexus)

What does this concern? What edits need to be cleaned. No, I haven't looked yet. I use TESEdit to tweak my mods.

Just let TES5Edit take care of it. Load AmazingFollowerTweaks.esp in TES5Edit > right-click on it > Apply Filter for Cleaning > right-click > Remove "Identical to Master" records > right-click > Undelete and Disable References > Close down TES5Edit > Choose to save the edited esp