Not just too big, but simply it's ergonomically bad.
First of all the command guides are split up and are located on both sides of the screen. When you have a new player playing the game for the first time, this makes it more difficult to adjust as you'd have to look left and right just to get used to the controls. Granted that this is not a problem for experienced players, but at that point, most would turn command guides off completely. So as a beginner guide, it's completely off the point. Personally, the existing guides are perfectly fine on the middle right side of the screen.
Next, moving tech and the armiger bars to the right side is also not a good choice. It's just making more eyework. Action games need to focus the eyes on the center of the screen where the action is happening as much as possible, otherwise it becomes a situation like FFXIV where is 95% looking at UI and 4% looking at numbers and 1% actually looking at the boss.
HP gauging isn't as important and you don't really look at it that often, unless it's a game that requires HP management. Which is why visual indicators are present when in critical HP.
Also, from what I understand, you switch through weapons, magic and items etc using the left and right buttons. This is actually pretty bad design in today's standard. Like you would need to scroll through multiple weapons to get to one and what if you go trigger happy and press too many times? Things like weapon switching need to be snappy and instant, which FFXV does good at as it is.
There are a lot of things. But gotta get back to work.