I played with Challenging AI
1) All AI players kept declaring war on me and then asking for peace 20+ turns later (sometimes sooner) just to declare war again a bit after that. I never seen a single unit come close to my areas. Even later when I was more spread out through the map and actually had their areas close they never attacked me.
2) During combat enemy kept attacking my Golem with most of their attacks although he had most armor.
3) AI kept telling me they are casting spells on my units but the game didn't show me which units were being attacked. I had to search afterwards for it. If you are going to interrupt my game with useless posturing from the AI at least make it somewhat useful
4) The game still suffers from mouse lag when holding ctrl and trying to select all my units that are inside the city. This was happening back in original game and all the way through all expansions.
5) Autoresolve of fights is funny. I fought that Stone boss monster (don't remember the name) and he wiped my full stack full tech high level troops+lvl 17 warrior hero with ease. I had one damaged archer squad with fire bows left. I clicked autoresolve to end this mockery of combat because I had no chance to beat him and to my surprise I won the fight with these archers surviving although they would never do that if I stayed.
6) More bugs that I cannot remember at the moment.
I didn't play LH since it came out where I played one game and lost the will to continue. I must say I expected more from this game and certainly less bugs after all this time.
This game is so much less fun to play then Civ5, it is a shame. I liked Master of Magic more then Civilization at the time. LH lacks either more interesting combat at least the complexity of HoMM or more interesting Civ building mechanics of the complexity close to Civ games.
Spells is only thing this game has over both but they don't feel needed or wanted. I had 1500+ mana by the end of the game.
If spells were implemented in a similar way Policy/Ideology/Religion is in Civ5 they would be so much more interesting and useful.