I actually liked FFXIII's battle system. Its just the story and most of the characters I didn't like.

I really enjoyed the battle system of Final Fantasy XIII (it's probably my favorite aspect of the game). It really shined during certain Cie'th Stone missions, where you had to use specific paradigms, skills, shift timing, staggering, chains, and so on. I would say that the battle system's only flaw is that there weren't enough encounters to force people to learn all of the battle mechanics (much of the optional content is where you really had to learn the battle system), which, now that I think about it, isn't really a battle system problem.

I don't enjoy getting to Nautilus Park, where apparently everything is normal, and getting teased by tons of chocobos and not give me any minigames or a freaking chocobo race to do there.

It was a fuck you (and a big fuck you Sazh too, considering what happens ) and I didn't welcome that. xD Change sometimes is a bitch.

Why compare FF13 vs Chrono Trigger like these have the best battle systems?  Chrono Trigger has a good battle system, Final Fantasy 13, they try to make an action oriented battle system with some strategy involved, I'll admit that, but it's just too repetitive and boring.   There are a lot of great battle systems.  Below are a lot of different standard RPGs that have battle systems that are more unique than the standard style.  I mean there are games like Breath of Fire 3 and 4, Xenogears, Xenosaga 3, that uses somewhat close to the standard style but have good battle systems, but I listed only those that have a unique style to them.

With people talking about the same few select RPGs, it makes me question how many RPGs they've actually played.  Square Enix has an amazing amount of high quality titles during their past glory days, but even then they're debatably not the best. 

Final Fantasy 10-2
Shin Megami Tensei Press Turn  http://www.youtube.com/watch?v=ayH3ePJcWJ4
Persona 3/4 system  http://www.youtube.com/watch?v=MbHI0S073hQ (first boss is 1v1, but team rush after all enemies knocked down.)
Grandia  http://www.youtube.com/watch?v=LcZJPRHMuhk
Tales of 2D system  http://www.youtube.com/watch?v=SqCDKB3PHjA
Tales of multi-line linear motion(and all advanced versions.)  http://www.youtube.com/watch?v=JrI7i0Qu-Q0
Various Star Ocean systems 
Legaia  http://www.youtube.com/watch?v=bHseUeVJtJM
SaGa 
Shadow Hearts  http://www.youtube.com/watch?v=bmYeHdwOpfo (Judgment ring is kind of meh, but adds variety to a simple combat system.)
Breath of Fire Dragon Quarter 
Wild ARMs HEX system  http://www.youtube.com/watch?v=3wa8G8mtSoI
The super repetitive Valkyrie Profile system  http://www.youtube.com/watch?v=lBspCjTvb-4

If the first time you played Chrono Trigger was on a platform other than the SNES and year after it was released, your opinion is likely going to lack the context of the era and how they compare to other RPGs of that era. You can't expect a SNES RPG to have a massive real time action heavy battle system like FFXIII.

The cutscenes were poorly written. The story was poorly told.

The fact that you have to read this

...to get what you need out of the story goes to show what a poor job SE did. I think that some of the enjoyment is lost with FFXIII if you don't read the datalog, but it shouldn't be that way. You shouldn't have to read walls of text to get the full context of the game.

In contrast, Chrono Trigger is excellent on ALL fronts, not just its battle system (which btw you are comparing games from two totally different eras). Story, characters, gameplay, music.... it has it all and that's why it is so highly praised.

FF13 also has a really repetitive combat system.  The second post you'll see someone state they play it manual only, and that's how you have to play it sometimes if you want to play most efficiently, but even when playing manually you have a variety of skills and other than synergist and saboteur only one or two of those skills will be useful depending on your situation. 

It's not like playing the game manual makes the gameplay change or anything like that.  It's people who try to make you feel like you're playing it wrong   The ones who have to feel like they're superior gamers when they're probably not.

Don't make me unfriend you.  I'm j/k. 

FF10-2 had the best version of the ATB system, a pretty good system, and while I didn't like the world map in FF10 as it was point A to B the entire game, the world map is actually good on FF10-2 because you start with the airship and go to different areas.  The world itself isn't so linear at that point.

I think Final Fantasy XIII's problem wasn't that the battle system was repetitive or boring, but that most of the encounters in the game were designed to be easy enough for most people to defeat, regardless of how well they utilized the system.  For example, trying to defeat the Adamantoises required specific paradigms, manual spell casting like Bravera, Faithra, etc., staggering the enemy's legs, debuffing, maximizing chain bonus for damage, and so on, so it required a certain amount of planning and real-time strategy to kill them efficiently.  In contrast, much of the story could be progressed without having to rely on such advanced uses of the battle system.

Obviously Square-Enix has to balance the difficulty of the game to make it accesible for the fans who play the game more for the story, but I think that the story needed more encounters that forced players to actually learn the battle system.  Instead, you could get through most of the content with simple paradigm shifting and auto-battle, where some of the criticism was understandably leveled at.  In my opinion, it wasn't so much the battle system, but the encounter difficulty and design that hurt its combat.

That's the problem with the battle system.  You can't have only a string of boss battles.  It's just not a very good battle system when you combine the fact that you actually have to have normal battles in there as well.  Even with the boss battles though, like I mentioned a few posts above, putting the game on manual, you're only going to use a specific amount of attacks per class.

Sentinel youl'l only use two to three, Commando only one or two, Ravager possibly just a single attack, Medic one or two, and only Saboteur and Synergist are the ones where you're going to cast spells like Haste first, then the other useful buffs, while Saboteur you'll probably have as the other two characters since by the time they're done casting, you'll have the Synergist spells that are useful for that battle. 

Boss battles that have no elemental weakness or strength, thunder is the fastest spell, so as a ravager, casting nothing but thunder gets you quick access to filling your ATB again, making it far more efficient to use than other spells.  Kind of breaking the reason to even bother with other spells and skills in the ravager line up in a single enemy boss battle.