Rhyming is a tool, like meter and metaphor. You learn how to use it to best effect. For example, internal rhymes are very powerful, mainly because they ar eoften not noticed the way end rhymes are.
If a rhyming scheme interferes with the impact and velocity of a song's intent, though, then it should be cast out. All the technique in the world only exists to augment communication. Technique being held as senior to communication is a waste of effort unless you are just practicing discipline for the sake of learning how to do a technique well.
You should be able to write rhyming lines at will, and then not do so when it suits your purpose not to.
As for rhyme schemes, they are usually complete within the individual verse. Requiring some linking rhyme from the first to the second verse (such as "all first lines must end in "...tam") is arbitrary, and arbitraries cut communication. There's a rule for you if you want one!