Tips for interesting mods

I played a few runs of the RogueTotalWar: Warhammer Spire mod and found out that modding is easier than ever. It got me interested, do you have suggestion for other great mods?

I know that SFO is one of the more famous one but I feel like I have more than enough units to play with (it probably does something more as well). I know there are also some mods for new factions and again, unless the factions bring something unique to the table I'm not too interested.

But any mods that change how the game plays, wacky mods that are fun for a single run at a campaign or something like that.