I always felt that there wasn't enough range in difficulty in either the base game or most mods. To that end, one of the things my mod
Reaver's Harmony sets out to do is improve accessibility with a wide range of difficulty settings. Beginner difficulty in Harmony
*should* be significantly easier than beginner difficulty in the vanilla game, however I haven't had enough testing or feedback to say for sure how easy it really is. If you'd be interested in trying it out and giving me feedback, I can help tweak the difficulty to suit your needs, and I would much appreciate the testing assistance!
shameless plug I knowI've also found a handful of mods which seem to be easier than the base game. Check out some of these:
Xtreme Measures - makes tanks especially strong, lots of new weapons ||
easiest mod I have played yetEqual Terms - very focused on weapons and weapon balance ||
I haven't played it but it looks significantly easier than vanillaUNEXCOM - huge megamod rich with many features ||
not easy per se, but gives you so many options that it might be easy depending how you play