So obviously, a fly rod must do what it was meant to do. That's why you should try many different types of fly rods so you know what actions, weights, lengths, etc will work best for you. How does the rod function for you when you cast a line with it? This is "where the rubber meets the road" for a fly rod. The most beautiful rod in the world would be a waste of your time if it didn't enhance your fishing.
So a rod's looks are secondary & not as important as how it functions, right? Maybe in a perfect world but in reality, no, not really. That's because we all judge a fly rod by that first impression of when we first see it - and that, friends, is based solely on looks. It's human nature, & as far as fly rods go, it's normal.
The first time we see a good looking rod we make certain assumptions about it. If all that care, skill, & attention to detail went into making the rod look good, then it's a pretty good bet that the same level of craftsmanship went into every aspect of the rod - the taper, the making of the rod shafts, etc. This isn't always the case, but it usually is.
As a custom rod maker it's my job to bring my client's vision of a fly rod to life. Through doing this I learn a lot about what looks good & what doesn't. It's in this collaborating with folks that I get to try out different things - stuff I never would have thought of on my own. Regardless of how a client wants their rod to look, it's my job to produce that the best way possible. If a client wanted, say, polka dots on their fly rod I'm not sure how I would do that, but you can bet I'd figure it out & put the best polka dots I could on their rod (please, nobody ask me to do that!!).
So how a fly rod looks is important & it's not shallow to think so. No, looks alone won't save a bad fly rod but without it you probably won't feel like you got your money's worth when you bought it. I see no reason why we can't have our cake & eat it too - a fly rod that looks & functions good.