I'm cool with bastion rules being a part of the new DMG. And because we're discussing a playtest, I'm positive the rules will evolve and improve before the DMG is published. I'm not worried. Although, I'd rather them call it the "stronghold" system, sounds more classic D&D to me.
But the new DMG needs more guidance and support for the pillars listed as important to D&D, but that have not been well developed. Travel and exploration, and social interactions. Other companies are innovating in these areas, WotC should too. And who knows, maybe they are planning on just that.
Really looking forward to Cubicle 7's "A Life Well Lived" (currently in crowdfunding) and their "Uncharted Journeys" (which is out, I just don't have it yet).