Gekirindan is one of those games that has a neat concept, is visually interesting, plays well, but it isn't good.
It's the all-too familiar case of style over substance. This is a criticism that isn't limited to high-budget AAA art-pieces or random indie obscurities. While arcade games are short, they tend to be difficult, and/or have a lot of depth. Gekirindan is definitely short. It's perhaps the shortest shmup that comes to mind. It's also extremely shallow, dull, and poorly-paced.
Part of what makes for good pacing is actually establishing it in the first place. From the first stage of a game like Dodonpachi, players have an idea of what to expect in the future. Gekirindan's time-travel concept allows for entirely new enemies in each of the five stages. Stage 1 takes place far in the future, but then stage 2 is set during WW2, with stage 3 taking place in 1999, and so on. In a way, it's impossible to really set a pace. The player goes through an entire stage with certain expectations, but then the next stage does a 180, and then everything becomes confusing.
So what does Taito do about this conundrum? Well, practically nothing. The first few stages are absolutely boring. Things start to pick up around stage 4, and then 5 is just a slog. Every now and then, there's a little uneven tension, but players are more likely to be shocked than anything. They suddenly realize that they're playing a 2D shooter, and that maybe they should be dodging bullets or something.
Speaking for myself, if I'm playing a shootemup, I would prefer to have very few breaks. In-between stages? That's expected. Sometimes during a stage, there's a brief moment where I can catch my breath. Stage 3 of Ketsui, right before the battleship, that's exactly what I'm talking about. Gekirindan never establishes its pacing, so it's almost entirely a break, with slight pockets of action. When the pacing is non-existent, I can't get into a rhythm. Whenever I see enemy bullets on-screen, I freak out.
Honestly, it's pretty embarrassing. As easy as this game is, I still haven't cleared it without continuing. I've reached the last boss once or twice, but I usually make a critical error in stage 4. While deaths aren't nearly as punishing as they are in Darius 2, they do just enough to put players in a bad place. Next thing I know, my ship isn't strong enough to destroy the stage 5 mid-boss (for the 1up), and eventually I fall apart.
I've 1CCed more difficult games. This isn't a brag (ok...maybe a little), it's more of an observation. Why am I clearing those games and not Gekirindan? It's because those games are appropriately paced. There's a clear trajectory when it comes to difficulty, instead of peaks and valleys. These games are simply more fun and satisfying to play, so beating them feels like an accomplishment.
I suspect that if I finally 1CC this game, there won't be any fist pumps, yelling, or exuberant cheers. Instead, this will be my exact reaction.