If you use the .it format (or some other tracker formats), there is a jump instruction that can be used to create continuous tracks. Write your intro patterns, then your chorus and verse patterns, then a jump instruction pointing to the beginning of the chorus.

Of course, using that technique, you can’t transition between songs, or to an outro…It’s a shame that tracker formats don’t have conditional jumps, that can be activated/deactivated by an external process during playback.