It’s even better than that: there is a little over four decades’ worth of games, in fact. :) There were plenty of bangers in the period 1981-1996.

Just as long as I can still keep downloading standalone installers for both existing and future titles.

I’m playing through it now, on and off, for the first time. I love the lore, the plot, and the environments. I also like the slow but continuous progression and variation of enemies and powers. But the combat feels like a bag full of chocolate: it looks wonderful at first, but after a while I’ve started to get sick of it. I could use fewer (or even no) random encounters, if only they weren’t necessary to allow for grinding.

One thing that takes some of the shine off the whole thing for me is the way that lore pickups are handled. When other “timely” things occur, one of your menu buttons is temporarily repurposed as a “do exactly that right now” button, so why not lore pickups? Especially because the lore is often best consumed in the time and place where you find it. But because actually reviewing it requires me to go through mutiple levels of menus every time, I usually put it off until I have several waiting for me.

Almost as annoying is the fact that for things you can experience within the game world (movies, videos, and tapes), the item will still be marked as “unread” in the lore menu system until you review it there, even if you stood still in the game and waited for the whole thing to finish. Since they’re already in a separate lore category, I think it’s safe to risk using a simple algorithm (for example, the player stayed within X distance for 95% of the total runtime, without an enemy encounter) to mark an item as “read” in the lore list.

Landstalker is usually at the top of my list for these things, but I took OP’s list as already being definite plays, so I skipped it. 75% of OP’s list would be near the top of my list.

This is the first “What should I play on early Sega?” thread that already has almost all my favourites. In fact, many of them are in OP’s list. But to reiterate some added by other commenters:

• The “Strike” games (Jungle, Desert, and Urban)
• Flashback (I agree that the MegaCD version is the best single version, but the fan community has been building a Frankenstein’s monster from the best parts of every version; I forgot the name of the project)
• Wonder Boy III: The Dragon’s Trap (SMS)
• Wonderboy in Monster World (MD)
• Quackshot (MD)
• Rock ‘n’ Roll Racing (MD)
• Sunset Riders (MD)

I don’t think anyone’s yet mentioned:

• The Immortal (MD)
• Golden Axe Warrior (SMS)
• Arcus Odyssey (MD)
• The Lost Vikings (MD, although I played the PC version back in the day)
• Micro Machines (MD)
• Crack Down (MD)
• Gain Ground (MD)
• Alien 3 (MD)
• Addams Family Values (MD)
• Monster World IV (MD, although I haven’t actually played it yet)

And a few more that I’m fond of, but I either can’t remember them clearly (other than that I enjoyed them at the time), or I’m aware that I can’t separate fact from nostalgia, so YMMV:

• Sword of Vermilion (MD)
• Light Crusader (MD)
• Robocop vs Terminator (MD)
• Predator 2 (MD)
• Cosmic Spacehead (MD)
• D&D Warriors of the Eternal Sun (MD)
• Atomic Runner (MD)
• Techno Cop (MD)

An honourable mention to Cadash (MD), which is a solid attempt at a port but sadly can’t really hold a candle to the arcade original.

I’ll give you the same advice that I give myself whenever I feel this way: There are already more genuinely good video games in the world than you will be able to finish before you die. If there’s a “classic” that you feel the need to experience, but you give it a solid chance and it’s just not “clicking” for you, put it down and move on to something else. You’ve tried it, that’s enough. Between all the games that exist, and trying to live a somewhat rounded life that has more than only games in it, you simply can’t get around to all of them.