Its underwhelming punch has less to do with its age and more with its execution. First, it's episodic, so don't expect a running plot until maybe episode 14. Which, episodic can be charming if done well, but...many of the episodes seemed to be done just because they could, and didn't leave much of an impact on me. Some episodes were predictable, and I grew more and more tired the longer I watched it. Still, I wanted to see it through to completion, which was why I kept going to the end. (And surprise, surprise: there's not a satisfying ending to be found. I won't say loose ends aren't tied, but there's a lot more ends just flailing in the wind.) If you can last until episode 14, you'll be treated with reoccurring characters, some deus ex machina moments, one episode with pretty decent psychological horror elements, and a cute scene or two from the main cast. Maybe, if you squint hard enough and tilt to the left, you won't notice how the plot drags in the latter half, and how the big, bad surprise ends up crunching in your mouth like rotten blueberries on a summer evening.
Then there's the characters. I was originally going to criticize Kantarou harsher, because god, his treatments of his summons ranges anywhere from callously flippant to borderline abusive. But Kantarou is, while incredibly selfish, pragmatic in ways that don't really stand out until you get to know him a bit better (albeit with contorted reasoning). You'll just have to suffer until you get there. Then there's Haruka, who does go through phases of character development in the story. He's who you'll probably want to cling onto to keep your sanity while watching this.
...Then there's the other two, the messenger pigeon and the girl who serves absolutely no purpose except until plot calls for it. Of all the characters, Sugino and Muu were probably the most enjoyable. They were meant to be comic relief, and they did their job brilliantly. But they were still lovable in all the ways that counted. They, along with Haruka, bring the best out of the show.
Last, for an anime that has been compared with various other BL series, there really isn't much in the way of fanservice. There IS something sprinkled here and there, but there's just as many moments where the characters become tangled with other affairs, some of them questionable by today's standards. If I was watching because of that, I'd be sorely disappointed.
Conclusion: Tactics was probably an anime that would have performed decently in the 00s. Standing on its own two feet, though, it pales in comparison with some of its older and younger peers even in the same genre. This is largely due to its incomplete plot, its predictable episodes, and its flat characters. Most likely, you might be interested in the premise and start watching it, but it'll tax you until you drop it somewhere in the middle. It is for that reason I struggle to recommend this series.
