What a lot of people fail to realise is that HeroQuests are not about world-changing rituals. They can be, but they are incredibly rare and have only been done by a few people.
I'm not sure that "fail to realise" is quite the way to put this. "Don't agree that" perhaps?
Want to kidnap a bride from a neighbouring clan? There's a HeroQuest for that.
Want to kill your Overlord? There's a HeroQuest for that.
Want to rescue someone kidnapped by trolls? There's a HeroQuest for that.
Want to get a shiny new sword? There's a HeroQuest for that.
Want to cure someone of an incurable disease? There's a HeroQuest for that.
Want to bring peace between your two sons-in-law? There's a HeroQuest for that.
There are people who play like this: doing a Hero Quest for
everything ("okay everyone, dinner's over! Time for "Voria Washes The Dishes Till They're Sparkly Clean!"). I believe, however, firstly that since time began most important events take place in time, second that Heroquests cannot and should not overwhelm free will unless free will is specifically hazarded, and thirdly that they lose all sense of specialness if you do them all the time.
In the list above, I would use Hero Quests only for curing an incurable disease. Minor Heroquests might be used to gain magical support for the others, but unless the trolls/neighbouring clan are holding the prisoner/Bride on the other side, you'll still have to go over and get them even once you've gained your magical, otherside support to your efforts, unless your Overlord meets you in the quest you'll still have to slit his gizzard for real, and even with the mighty persuasive powers you have gained your sons in law may yet tell you to mind your own business.
Actually the sword may be another exception. I cannot persuade myself the Soltakss uses Heroquests to go
shopping, so I assume he means enchanting the sword. Thats something I would use a HQ for too.
I believe that Glorantha has a mighty magical history, but the focus is on the mortals these days, since there were days in fact. On mortals in general, and PCs in particular. Gods act in the world through worshippers: Myths act in the world through Heroes. Heroquesting can give insight, power and magic, or deny the above, but it can't actually do anything in the real world unless heroes actually do them.
That's an Orlanthi "can't" of course. But when it does, in the longer term it is almost always Bad News.