One of the reasons why I got into (and will always love) Skinny Puppy forever is the fact they didn’t care much about established song structures. I remember an old cEvin Key interview around Last Rights time where he said that he had no interest in exactly knowing what was coming next in a song. I 100% agree with that.
While for some (usually pop/rock) genres it can be great to have the basic formula (hello AC/DC, Ramones, etc.), it can also become terribly boring really quickly. Speaking of AC/DC and Ramones, you basically only need a max of 10 songs and you know all there is to know about their 20 or 30 albums.
Consider what 95% of mainstream songs are. It goes something like: intro/ verse 1/ chorus/ verse 2/ chorus/ bridge/ chorus x3/ the end.
Urgghhhh
I like the fact that, with instrumental music, you’re more likely to have surprises and innovation.
While a build up in a song is great, I would hate to have someone listen to my songs and know exactly what to expect next.
So do whatever you want. Start with something crazy and end up like an ambient song. Repeat the same section for 3 quarters of the song and fuck it up at the end. Have 2 choruses and no verses. Everything is possible
Edited to add: thinking a little bit more about it, I do quite dislike the concept of a “payoff” in a song. For me it makes it sound like your song is useless except for the 20 seconds where there’s a riser or a drop or a solo, whatever, the "payoff’.