I think this is my problem with most of these games: When I look for entertainment, I want something that will engage my mind, and not just my brain. I don't demand a storyline of any particular quality in my gaming experience, but I demand an experience, not just a test. Tetravex was as fun as most of these games have been but, now that I'm looking at the end of the first round of games, few of them have been what I consider a video game.
Super Mario Bros. doesn't have a storyline in any real way, but it's fun. Because I'm constantly doing stuff. My mind is engaged, trying to figure out the best way to do something, working with that whole hand-eye thing to make it happen, taking in what I'm seeing and adjusting accordingly... I'm playing. When I'm looking at a Tetravex screen or playing GNU Chess, I'm just... looking. And thinking. I'm not saying chess makes for a bad game, mind you. It just makes for a bad video game. When I'm playing it in person, I'm looking at the person, I'm talking at 'em (trying to distract them, because I suck at chess), I'm engaged in playing them. There's no real play in Sudoku or Tetravex or Klotski or Mines.
I think that's the difference between the games I enjoyed and the games I didn't. The stuff that was fun (Four-in-a-Row, Five Or More, Same GNOME, etc.) allowed me to keep reacting in a semi-fast-paced sort of way to the things that were going on in the game. Since they had no real story or progression, they weren't anything I would choose to play a lot, but they did at least let me play. The games I didn't care for didn't allow for that. Most successful casual games (all of the ones I can think of at the moment, anyway) also allow for that. You get to do stuff, on the basis of what's happening, instead of simply planning for stuff.
Thankfully, this chapter of my time with Linux gaming is over. While the next chapter promises to hold just as many godawful mind-games as this one (I've looked at the list) there are, at least, some games that look promisingly like what I have come to consider a video-game. Starting with the first one on the list, Abuse.