Only way to get out those strong flavors is a good soak in alcohol for a few hours. Some say boiling in water for a good 15-20 mins may work too. I have a protank that has had absinthe in it - and I swear I can still taste it after months of different flavors going
through it.
But yes, when changing flavors, you can really just fill it up with a new flavor and
vape it - I've found some great combinations (and some not so great too) by mixing the last bit of a clearo with a new flavor. If you wanted to rinse you can, just shake it and blot dry and go again.
First hit or two may be a little weak because of the water in the wicks, but it won't do any harm.