Any cool indie RPG/Strategy games with scenario/map editor?

I have a thing for modding. Recently, commerical games are not meeting my needs and I am thinking of exploring independent games which have scenario or map editors. Anyone have anything to recommend?

Look into Blades of Exile and Blades of Avernum from Spiderweb software. I played with their scenario editors about 8 years ago and had a blast. They might be a bit dated/simplistic for what you are looking for, but it’d be a good place to start.
Also, look for Battle for Wesnoth. A bit like the old game Age of Wonders, only free and highly modable.