No. I am not interested in score unless the score systems are very intuitive like it is in MoF. Memorization < Improvisation.
Why? It is the
solution to the very problem you're complaining about. Obviously, stages are arranged (approximately) in ascending difficulty for pure survival, so there will come a point when the least challenging stages won't seem very challenging to you. This is when you insert the additional challenge of chaining to kick it up a ton of notches, so that the early stages are back to a more interesting difficulty level. This applies for pretty much every game Cave has made (and most modern shmups) - it's very, very, very
difficult to really have maxed out (and so have finished with) a stage in a Cave game, even first stages for the most part.
Regarding improvisation: your need to improvise will disappear the more you play the game and learn how it works, eventually only remaining in the patterns that can't be memorized due to having random elements like Hibachi's patterns. I would say that a good and in-depth knowledge is the most important thing for being good at any given shmup.