I stopped worrying about page count long ago. But, I get how depending upon how one were to publish it, it could be a real consideration. Everything I've published (which is only a few) have all been digital only releases. The page count on the PDF doesn't matter. And the amount of text content in an FG module really doesn't matter either
Customized no, but adapted yes. I think there is a strong difference in the words. You don't need to customize the locations, or the names, or motivations or events. But you do need to adapt the challenges to the party. (Semantics I know, but I think it will be important in marketing and customer adoption.)
By having different sets of NPCs, you can adapt a combat encounter to martials, ranged, casters, etc. All by changing up which set(s) of NPCs you use at a given time.