“or can it even be done on a whim of desire of the mispallel?”
I dont really understand this. IT is hard for me to imagine a scenario where a person changes what he has done for a “long time” based “on a whim”
If the Shul is closer, further, more talking, less talking . faster davening, slower davening. These are all thing s some people look for in Shuls, I wouldn’t say they are a “whim”
Way the pros and cons of each and do what is best for you and yours.