Some examples I came across. I know the AI is flawed at times, but it somehow doesn't really bother me.
Good:
I loved the Fire Emblem series; especially 7. Sure, you could be screwed over by the random number generator at times, but there was always a fixed chance for things to happen. Got criticalled by a bandit that had 2% chance? Tough luck, but you'd knew that from the start. Gain 1 hp after you level up? Tough luck, but the percentage of stats improving is fixed. On top of that, it was challenging and unforgiving, but didn't rely on secret buffs, or any other unfair advantages.
Similar, I loved the advance wars series. Yes, the AI isn't too smart and could be abused, but similar rules always were in place. Each time, the AI starts off a little stronger, but still, there are always several ways to complete the mission. Also, one of the few games like Fire Emblem that respects the rules of "Fog of War".
Bad:
Most Total War games. Especially in Rome 1, turning up the difficulty could make things near impossible to play as on the map, it meant cities couldn't become larger than "x" before they would revolt non stop; especially if they are located further away from the capital, which is not something you can avoid the moment you expand (and are expected to). In battle, the units of the AI received insane bonusses, which meant even your elite troops like praetorians could lose out to ordinary peasants. In other Total War games, the AI would receive economical boosts so they can keep producing armies and don't go bankrupt because of the inevitable upkeep problems. Especially in Medieval 2 and it's mods, the only way the AI could make things challenging (and feel like a real grind), by spamming stacks at you. The battle AI always had it's flaws so it's sort of understandable why difficulty can't be fixed there.
A lot of RPG games:
At times I love to play RPG games and even go as far as to try out RPG maker games. Apart from a lot of unrelated issues with RPG maker games (terrible plot/no balance/unlikable or stereotypical characters etc.), a lot of these games are made "hard" by either requiring players to grind for sometimes hours, or by spamming "status effects" in battle, which means around the 33%/50% mark of the game, you keep running into bosses that fight just by stunning/paralising/poisoning/blinding/stoning/silencing/insta ko'ing/bleeding etc. you which means that at least 2 of your inevitable 4 party members are on "potion duty" or "status removing duty". It might be unfair at this point, but by now, I'm also rather sick of most games having the same kind of puzzles like an ice sliding puzzle, a light puzzle which requires shoving mirrors around and pushing objects from A to B.
Really on the fence about:
I really, really love Crusader Kings II lately. By now, I've spent closely to 300 hours on it already and no sign of stopping. However, a lot of major events for each playthrough/ruler/character are decided by the roll of a dice. You can influence most factors, but there's still a random chance you'll receive a blow to the head in battle, pick up some illness and die, or get thrown in prison by your liege at the worst possible times. The thing here, however, is that everyone/almost everyone playing the game (myself included) doesn't seem to mind as the "randomness" is what makes each playthrough or each character unique, which delivers the most hilarious results, like a lustful heir that studied a year with the pope, buying a necklace for the wife to "bring out the color in her eyes" after just blinding her, or just your inbred, craven, Hunchback bastard brother killing you in your sleep and then ruining your Byzantine Empire 400 years before it's time. The thing is that the randomness is so incorporated and accepted that it no longer seems to be an issue, despite the fact that people could actually call it flawed design.