I know this probably once again puts me into opposition to Kasnavada, but I'll stick to my point: Catering to niche audiences that can stomach a steep and prolonged learning curve will probably result in more interesting and memorable games than trying to make simple games for everybody.
Indeed, I simply can't believe that unless you're part of the maybe 10% of people that can and will stomach a steep and prolonged learning curve, you can't have interesting and memorable games. I know it's not exactly what you're saying but that is kind of what I understand when I read it.
What I believe is that for a game to be interesting and memorable, it must either "resonate" with you somehow (story, graphics, gameplay mechanics...) - which can happen to anyone and for possibly any reason - and / or have the possibility of having a "high skill level" of play, or "simply" just "higher". By which I mean like "go". A "go" Master will just not lose to 99,9% of other people when challenged. Despite that game being one of the simplest around. But, "anyone" can play and train in it and have fun.
So... that's why, when providing feedback, I focus on having the "broadest" entry point, enabling "high skill level" play and things unique enough to provide interest."My" definition of what "best games" are would be games where people explore most of the game, then find their own niche in it. Because you might have the "dream" game you're looking for somewhere, but if you don't ever get in it long enough to find it... there's no point.
Examples:
- If you're looking for "high level play with complex rules", for example let Kahuna play diff10 AI war. However diff 5 AI War (default difficulty last time I checked) barely requires deep knowledge of the game. Large entry point, niche for everyone. Actually with the amount of customization possible, it kinds of went overboard =). But we love it =).
- Eve online is the same, barely anything is required if you're staying casual in high-sec, even if the game will soon be boring, it does introduce you gradually to a lot of concepts before you start PVP. People wanting to start PVP from the start are in for a surprise though, as survival will require skills and knowledge you can't have, or people guiding and protecting you.
- Jagged alliance 2 I played, but not the modded version. From what I remember, the game mechanics are gradually applied which makes for a tutorial of sort, and the game was rather easy once appropriate precautions are applied. I guess that the mod is a more difficult game for people wanting their niche in it.
Other games in your list, I don't have - can't really tell.