Are most forms of beauty an aspect of our sense of patterns?   stance: most things we consider beautiful are so because they match a pattern:
Anything we consider art is based on the artist's ability to match something within us that evokes an emotion. Many of the things that we consider beautiful outside of the realm of art (e.g. fractals, algorithms, arguments) are things whose patterns are inherent, or which describe something else in an elegant manner.
I would argue that the part of our mind that experiences beauty does so in reaction to the identification of a pattern, either external or internal to our self.