If you were a fan of RPGs in the 90s, chances are you've played at least one game with an
ATB system. The Squaresoft of old pioneered this system in Final Fantasy IV and continued it's use through the next whole decade in the series, along with additional titles like Chrono Trigger and Xenogears. When I first experienced these games, the battle systems created a sense of speed, finesse, and urgency for unmatched in any turn-based combat I've played.
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However, after going through my library the past few months and replaying old jrpg classics like those listed before, I've realized
I do not care for the battle systems at all. In my opinion, these battle systems heavily relied on high agility, powerful attacks, offensive spells, and the occasional "heal all" item/spell, with little room for strategic planning and character buffs/debuffs outside a boss fight or two. They created an illusion of fast battles when in reality they simply fixed your movement speed. On top of it all, it become flat out frustrating to pick the right move under the pressure of being "Supernova-ed" by a tough boss. It was then when I came to the conclusion the more traditional turn-based battle systems like those found in Final Fantasy X, Xenosaga III, the Shin Megami Tensei series, and the Dragon Quest series are more engaging and satisfying.
I think you are conflating different aspects of the traditional Final Fantasy combat experience. The ATB system at its core is nothing more than a system where a character can act when their ATB gauge fills up, but time is constantly moving. All of the other stuff you mention: reliance on powerful attack spells and special moves with occasional healing, is due to entirely unrelated parts of the game design. Those things are the result of several factors of game design found in the series that would be just as true if those games took place in a traditional turn-based framework.
The simple explanation here is that games such as Final Fantasy VI and Chrono Trigger are, by design, extremely easy RPGs. They are designed around the idea that the player will murder everything with powerful multi-target attacks, then heal your characters up with powerful full-party healing. Despite being turn-based games, Final Fantasy I, II, III, and X use fundamentally similar strategy to Final Fantasy IV and VI. This is due to some common design aspects of the Final Fantasy series: there is generally a lack of aggro control, most party members are reasonably tough enough to survive several hits, healing magic is more efficient when used on all party members, multi-enemy attacks are commonly available, and spells and special moves can be used very many times (often are effectively unlimited in use).
BTW, Xenogears is a very different beast, and one that highlights many of the differences from the Final Fantasy series. First of all, you must have mis-remembered, but Xenogears is a pure turn-based RPG. It does not use the ATB system whatsoever. It uses the very common system used by FF Tactics or X, where characters who are fast take more turns, but there is no realtime game element. More importantly, it has a lot of notable differences from the Final Fantasy series in terms of those fundamentals I mentioned. For example, multi-target healing is much more restricted. FOr example, Citan can use multi-target healing spells, but it takes him an extra turn of set-up, making multi-target heal spells come with a significant delay. Billy has multi-target heals, but he is also extremely fragile (more so than most FF characters, relative to other party members). Furthermore, Gear combat in particular is very restrictive when it comes to both healing and using special moves. Fuel costs heavily restrict both healing and the heroes' multi-target attack skills, while the strong single target attack skills take multiple turns of set-up. This creates a completely different gameflow compared to any game from the Final Fantasy series.
Side note: Yes, I know Square Enix still use it in heavily modified ways as seen in Final Fantasy XII, the Final Fantasy XIII series, and Type-0. However, these incarnations share only the most basic functions of the games in the past (the gauge itself in most cases) and could almost be considered entirely different beasts.
That is the thing: the ATB system
is that gauge. Final Fantasy XIII uses a completely traditional ATB system at its core. There are only a few key differences. First of all, the speed of the ATB gauge is significantly faster than usual for the series. Second, the player is allowed to queue up multiple actions, with more powerful actions having a larger time cost. To take these changes into account, the game utilizes AI control in order to make things more manageable. That's it.
The game includes a number of other significant gameplay changes though, which are independent of the ATB system. These cause the game to have a unique feel compared to other Final Fantasy games. Part of this is restricting healing to being single target only, while at the same time introducing a tank role that can control aggro. The introduction of the Break mechanic also completely changes how the player goes about doing damage to the enemy. However, these new mechanics are not dependent on being connected to FF XIII's version of the ATB system. In fact, they are fairly common in games that utilize other gameplay systems. Xenosaga Episode III, despite being a turn-based game, used a Break mechanic that was pretty similar to FF XIII's in many regards.
Now, I can understand being unhappy with the feeling of being rushed during critical moments in a boss fight under the ATB system. That added stress is the main point of the ATB system, and I can understand that some people don't like it. That's perfectly fair. However, the rest of your complaints about the ATB system don't actually have anything to do with the ATB system itself, so much as the fact that the Final Fantasy series is an easy series with a very low skill requirement designed to appeal to new RPG players and casual fans of the genre. Even then, there are a few Final Fantasy games that have a lot more gameplay depth than others, and these really show off the strengths of the ATB system. Final Fantasy V is a good example of this.
