Yes, 'taste' is incredibly complicated and there are
many elements to it, from texture, to smell, to temperature, to emotional state, to blood pressure, etc. We are still discovering what tastes humans actually possess and where they possess them in their bodies. What you are classifying as 'taste' is many things other than the definition of taste; you include smell and texture in the lists above. Especially on the bitter part, human sensation of bitter is highly variable from person to person. What you may consider bitter may not be able to be sensed by your customers and what you cannot sense may be tasted by your customers, hence why many confectioners tend towards a similar mean taste profile (pepsi/coke). You mention that things may 'taste like wood', this is a cultural association that you may want to be aware of. Try getting other people from other cultures/environments to drink your stuff and see if they also report these sensations. As far as 'drying out your mouth', this is again highly variable depending on hydration, humidity, personal preference, etc. For example, a friend of mine loves seltzer water for 'the burn', while I hate it for the exact same reason. I also drink my coffee black these days, but I will change my taste from time to time. Mostly I am just addicted to caffeine and coffee is the cheapest way to get the fix.
For more information on the sensation of taste and all it's myriad complexities, you may want to check out these resources:
http://www.ucdenver.edu/academics/colleges/medicalschool/dep... Sue is a world expert on taste, along with Tom Finger, and her work is excellent in every way.
https://www.amazon.com/Principles-Neural-Science-Fifth-Kande... The bible of neural sciences, though thick and dense, the sections on gustation and olfaction may prove useful to your endeavors.
Edit: Here are some other resources on how to modify your taste sensation to better understand how your taste buds work:
https://en.wikipedia.org/wiki/Category:Taste_modifiers
There is also a supplement that you can take that will elliminate your sensation of sweet for a few hours, but I forget the name
Lastly, to understand umami, try getting a few bags of chips of similar salt content and hold your nose the entire time. One of just regular Lays potato chips, one of something like Doritos, and one of those baked Parmesan cheese ships from whole foods. While eating them with your nose held close, try to recognize the changes in the umami taste.