FFV was a big disappointment for me too. I own both the Anthology and the Advance version, so I am a little familiar with the game, and I have played all the games in the main series besides XI. II lists at the bottom for me, but this one stays in the bottom 3 or 4.
As much as Final Fantasy games were not about graphics, (in my opinion) this one was still a disappointment. I concur that the monster design was uninspired and the choice of colors and designs were horrible. The bright pinks, greens, and purples seemed completely improper and rather annoying for me in the game. The story was terrible, you get no sense of urgency to slay Exdeath, nor any conviction to not like his character until the death of Galuf. Even then, the game has little motivation for you to beat it. The characters are plain and often irritating.
I do like the lightheartedness every once in a while in the game, but still, it is a severe letdown between IV and VI. It seems like they took a step backward, then took 3 steps forward for VI. The game could have been more amazing than it was.
I concur that the monster design was uninspired and the choice of colors and designs were horrible. The bright pinks, greens, and purples seemed completely improper and rather annoying for me in the game.
At times I liked the brightness but I do think there is a time and and place and it was way overdone and felt like they felt they needed to add it in way more than it actually did. Overall I see your point but in some minor ways I liked it.