I personally think they get better in some ways. Though widely praised, Symphony of the Night is a game with many faults. This doesn't mean that I think it doesn't deserve the praise, but in the flood of accolades, people often skim over parts where I think it should be heavily criticized. The thing is, what Symphony does well, it does so well that it's easy to shrug off the bad points. At least it is for many people.
Lack of difficulty.
A story that doesn't make sense, or at least leaves way too many crucial things unexplained.
A tacked on, directionless, and in many ways uninspired second half of the game.
Recycled area themes galore.
I could really go on.
I would recommend giving Aria of Sorrow a try. Of the Metroidvania games, I think it's the most... um, practical of the lot. The others aren't as easily appreciated based on practicality and basic standards, like cool bosses, approachable music, tight levels, cool stories, and all that. The actual really good ones appeal to me on a bit of a higher plane than that, mostly due to moods, feelings, and atmospheres that the game worlds emit, but I wouldn't expect everyone to appreciate something so vague, at least not in the same way I do.