The game is not remotely dumbed down. It has a very complex levelling and battle system, and there are a shit load of side quests that aren't empty (as in, there are a ton of sub plots with VA recorded dialogue, a purpose for each one). The characters all have depth, reasons for what they're doing and no plot point is useless (though there are a few plot-holes).
It's all about choice. You can choose how you want to level your characters, which roles you want them to advance in for the strategies you're going to use in battle.
If there was no strategy required, I would be able to spam auto battle all the way through, and you
seriously can't do that. If you choose to level the wrong roles or don't have the correct paradigms set before battles, it's actually very easy to get a game over.
The story is actually not bad. There was at least a running narrative this time, and the characters were finally real enough to care about. The only problem was TOO MUCH CHOICE leading to a slightly fractured narrative, but that's only me because I'm a completionist and had to do everything as soon as it was available.
You have 2 characters in battle, and another 150 monsters to choose from. This makes for some very interesting (and fun) strategic planning. I'm not going to pretend I don't miss having my 6 characters to choose from as in XIII or any other FF game, but what I will say is that I fucking LOVE taking a Tonberry into battle with me. It's hilarious and keeps the battles from getting stale.
If there's one thing I'm going to complain about, it's Serendipity. It just feels quite empty. The chocobo races are impossible to consistently win on the highest class without a totally levelled Silver/Gold chocobo, and even then they're repetitive. Not to mention my rage at trying to get that 7777 coins fragment. Literally just got 20000 coins from the exchanger and sellotaped L1 down.
Got my platinum trophy this morning. The game is worth every penny, and Square Enix have taken the complaints with XIII and actually implemented every single one.
The ending was a bit of a mindfuck, but it was still totally worth it. I wouldn't be defending it's predecessor nearly as much as I'm defending this, and that's because every fan complaint has been dealt with. If people want to keep bitching they have a right to an opinion, but I think
people that have played it from start to finish are pissed off because they can see they fixed what they didn't like about XIII, and they still don't like it. Which is a shame.
To be honest, the biggest mistake they made was calling the auto-battle button auto-battle. Having recently replayed VII and VIII, you're doing the same fucking thing for the first few hours anyway. Attack, Attack, Attack, Attack. You do the same thing at the start of EVERY FF game. Just attack to win. Hold X to win, as it were. Then you might have to cast magic once in a while to kill something new, or to heal. Technically speaking, XIII and XIII-2 actually require more button presses to do this, what with the paradigm shift before you press "auto-battle" again hahaha
.
EDIT: I've just re-read this and I would like to make it clear that I am in no way saying that this is the best ever Final Fantasy game, but it's still a damn good one. I just feel the need to vehemently defend it since a lot of people seem to have made the assumption it's just like it's predecessor when it's a completely different game.