As the title says, instead of seeing more prestige classes, I would like to see Archtypes for prestige classes. Archtypes for Dragon Disciple would allow for other bloodlines. Archtypes for the Eldritch knight could allow for school specializations or witch's hexes.
What do you think?
Depends on the PrC. Adopting Dragon Disciple for other bloodlines would basically require a full rewrite, at which point you should just write a new class. Also it might make them seem a little less prestigious.
I could see a 3PP offering this, but not a full Paizo product. Unless it showed up for special specific circumstances (like the Bloat Mage or Hell Knight prestige classes) since archtypes require relatively few words for what they do.
Making a variant version of a feature that is already rarely used just seems like a poor plan. However, I will throw out there, I had an idea for the RPGSuperstar of an archtype for Shadowdancer that removed the shadow companion and offered superior shadow dancing skills.