I noticed it on the workshop, but ignored it because I had no interest in having blizzard in civ.
Same.
If it's the one I'm thinking of, I gave it a try.
Interesting, but wonky and unpolished. The hero talent system was pretty clever- there were six or seven color-coded disciplines, each consisting of three basic skills and three advanced skills. To get each basic skill, you needed... hm. Either the basic skill before it, or just the corresponding basic skill on an adjacent track. To get the advanced skill, you needed the matching basic skill in that color. The clever part comes from the fact that each hero has a "starting" track that they had full access to, and then could only get adjacent skills by filling out their home track enough to support them. So a mage could learn warrior stuff if they wanted to, but it'd be kind of a long trek through all the skills they might not particularly want in the way.
Perhaps a diagram is in order:
So if you started at Green, you could get 1 right away. I think you had to get 2 to get 3, but can't swear to it. 4 required 1, 5 required 2, and 6 required 3. To get blue, on the other hand, required you to have points in green, so if you wanted Blue 3, you had to get Green 3. I forget if you also needed Green 6 to get Blue 6, or if Blue 3 would cover it. To move on to purple, you needed a similar foundation in blue.
But yes, very wonky. There was pretty much nothing to build but wonders, and the documentation wasn't very good. Normal units sometimes had mana, but couldn't actually cast anything as far as I was able to discern. The item system was particularly odd, since it jumped up pretty significantly in power and cost each age; you could also get items from defeating barbarian encampments, but those were less predictable.
TL;DR: The newest installment in the Civ series had some neat ideas, but I think they were rather clumsily implemented.
Also, is there a way around the difficulties I've had with waging war? You know, cities not really ever dying (seriously, why can't you march a military unit into an unguarded city anymore?) and not being able to move units into position as fast as they're produced.
Presumably so that taking cities is a major accomplishment, as opposed to a natural extension of having a bigger military in the area. In my opinion, that combined with units routinely surviving combat is a much better way of doing things. You can have nice little sieges now, as opposed to smashing your units against theirs until they all die or it becomes clear you're not going to make it with what you've got left.
So, you might want to try treating your armed forces more like little hero squadrons you level up and less like an unstoppable tide of iron. Might be more fun, whether or not it turns out more effective.