You could consider me a fanboi of the Final Fantasy franchise - so much to the point where I desperately tried to enjoy their horrible movies and find some shred of good inside of them. There are certain things that make Final Fantasy.... well, makes it Final Fantasy and I feel as though most of this was poorly implemented in this title.
Since I don't want this to be too long and there are so many issues I want to focus on I am going to make this a multi-part series. In this episode I am going to focus exclusively on combat - which, as you might expect, is a major part of the overall game.
combat is difficult to follow
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They were trying to step away from turn-based combat in this one and as far as I know that is the first time they did this. I could be wrong because I missed a lot of titles in between but this is the first one that I experienced that was live action.
The end result is that you never really know which enemy is where because the auto-camera is constantly flipping around to follow your movements. Since Noctus (your character for the most part) has an ability to instantly travel to distant parts of the "battle zone" and when you do this, it flips the camera automatically and many times this ends up with a tree or a rock or something completely blocking your view of the battle
oh great! Being able to see my enemies was making it too easy anyway!
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Magic changes are more realistic but dumb
You don't acquire spells based on a class like past installments (I actually really liked this aspect of the past games) you craft spells based on things that you find and then bottle them for later use. You can equip them to your pals in the group but i really recommend you don't do this because of friendly fire.
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The auto-reaction of your pals (except for Prompto) is to immediatly run up very close to the enemies in melee range so you throw a Fira spell knowing that it will do great damage right at the start aaaaaaaannnd you hit your own troops and kill them too. The effects of the "spell" also lingers after "casting" so when you follow up for a warp sword strike after your initial volley, you also set yourself on fire. While I will admit that this is more realistic than casting with impunity this is a fantasy game and realism be damned!
Most battles require almost no strategy
For a vast majority of the battles you can simply hold down the "lock on" button and the "strike" button and that's it. You don't even need to participate in the battle. When you run low on HP you just use a potion and then return to holding down those two buttons. Since you can't really tell what is going on anyway because of the spastic camera movement, this is often what you end up doing in battle. You want to use some finesse, but the design of the battles is so chaotic that anytime you get a bit confused you can just revert to holding down two buttons and wait.
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Previous titles, while they were in fact turn-based, required extreme strategy and also inventory and time management. Potions are available pretty much everywhere and are extremely inexpensive so there is very little reason that you would ever run out of them. I very rarely used anything higher than the original low-power potions all the way to completion of the game. This doesn't make sense and just seems like poor design.
You can't use "summons" except in pre-defined situations
One of the major aspects of Final Fantasy games in the past is when you introduced a new "summon spell" to your arsenal. Shiva, Ifrit, Titan, Leviathan, etc.. These were all wonderful additions to your offense that also normally had a beautiful animation that came along with their use and you could use them whenever you felt like it; they just had some manor of a "cooldown" or something along those lines.
The summons in FFXV are friggin gorgeous - they are quite an animated achievement to be honest. However, for whatever reason, you can only activate them during certain times of the game and even then it isn't up to you which one of them you are going to use. A flashing button just appears on the screen that says "Summon Leviathan!" or whichever, and then it gets used once you press the corresponding button.
If this is going to be the case, why bother having our trope acquire them in the first place? They may as well just have these gods interfere on their own behalf if the time and place that it is going to happen isn't up to the player.
tl;dr / conclusion
The combat in FFXV must have been a massive undertaking for the dev team over at Square-Enix and it shows. I can't even imagine how complicated the code must be for this but the end-result kind of appears as though they had a wonderful idea on the storyboard part of the creation process but then after running behind schedule for YEARS they finally just found something that doesn't crash the system and threw it out the door. it seems like an unfinished product .
Why they decided to completely abandon turn-based combat is something I don't understand why they would want to eliminate since a lot of the appeal of Final Fantasy as a whole actually IS that aspect of combat (you can activate "wait mode" which is kind of like turn-based, but is actually more annoying than helpful.)
The battles are horrendously easy and require almost not strategy or even knowledge of anything other than a few buttons. There are a few situations that are a bit complicated but these are mostly boss situations or you charging foolishly into something 20 levels higher than you in open world (you knew you didn't have a chance there noob.)
Overall, I have been extremely disappointed with this title and a lot of this is based on nostalgia. However, I can't really imagine a "new" player who has never experienced the groundbreaking games of the 80's and 90's enjoying this or feeling as though it was anything other than a mess.