If we're talking about the tea alone, then yes - taste comes first, followed closely by smell.
If we're talking about the global experience, then it has to be "all senses". Touch is especially important to me where the teaware is concerned. And the visual element is essential. You could drink tea exclusively with your eyes closed (and I think it would be interesting to see how much it affects enjoyment), but the colour of the tea and the beauty of the cup weigh pretty heavily for me!
On the e-yakimono site, Robert Yellin speaks at length
about what makes a good guinomi (sake cup) or tokkuri (sake flask). Now, he's talking about drinking sake here, not tea, but I think it would be interesting to test his words with different tea vessels to see how much they hold true for our beloved drink:
What makes a good guinomi or tokkuri?
Naturally it is a matter of personal taste. Aesthetic appearance, weight, balance, how it feels in the hand, and a drinking lip that is not excessively rough are the general points of assessment. [...]
Size isn't everything, either. The rim of a vessel - its thickness, texture and curve - will affect how a liquid distributes itself across the tongue and palate, thereby radically affecting the taste profile and fragrance. The artistic and aesthetic qualities as well contribute, if nothing else, by influencing the mood and atmosphere.