Personally, it was my least favorite. It was the first game that they used the ATB system in (I believe), and so I guess they didn't really feel the need to include much in that game besides ATB (which most later entries had, too) and the storyline. I thought it was a fine bare-bones RPG with reasonably memorable characters, but not much else. sweatdrop
I never thought it boring, the story had a solid premise, the characters were decently written, and given the age of the game itself, there was not a lot they could do about visual styling or anything like that. So many gamers today get so visually spoiled that they can't recognise a decent story anymore (Not implicating you, just making a general observation), and RPG's are solidly considered nerd territory because they are slower to get off the mark and don't have a lot of action for the most part.
As a fellow gamer whom has like many played Final Fantasy IV I won't be the first to admit that I did find the game to be somewhat boring and mediocre, however I will have to admit that Final Fantasy IV isn't nearly as boring as Final Fantasy VIII in my own humble opinion.
FFIV isn't that exciting, really. But I've played that game to death.
When I first got it for my PS, in the Final Fantasy Chronicles bundle, I hated it. I couldn;t even get passed the opening sequence. But once I gave it a try? I actually really liked how old school it was. I like that the characters had set classes and the game was actually hard. I've had the gaem for years, have leveled my character like crazy, and have even done a Rosa & Rydia only game, but I have yet to beat it. I'm bad for that.