" If the story only happens one way then why even have choices? " it is quite common situation so i look at single choices just as progression indicators
personally i am not an advocate for alt routes as i get disturbing feeling that i missed content and-or that i have to replay to get it (in some cases it is better to replay the game completely, in most - all that annoying save-load-check, go load previous route. burdensome). also it dissolves devs focus and instead of solid lengthy routes all those branchy small pathes occur.
so for that to work there should be path resets, event triggers, etc + very productive collective.