That seems like a somewhat random collection of points, so to step back from trying to deduce what they might or might not be doing, it is most important to figure out what you are trying to accomplish in precise terms?
Dry mouth could have any number of causes, so your time should be one figuring out what that is, rather than symptomatically treating it.
Tongue coating can change quite a bit from day to day depending on weather, what you have eaten, how much you have slept, etc. so from a deep perspective it is not always that useful.
Saliva flow is largely related to digestive function and control of stress hormones. So it will generally be less under stress conditions, more during meditation for example, slightly more with strong digestive qi, slightly less with qi deficiency. The entire point of Chinese Medicine is to get a clear idea of what it is you are trying to treat at the deepest root level, not chasing after more transient symptoms which will lead to ineffectual treatments at best.