This is one of my greatest frustrations with the current story. I know they aren't popular around here, but the Gatewatch (from Origins to Hour of Devastation) was at least consistent for the most part. Yes, Origins leaned on retcons a bit much for my taste (looking at you, Nissa) but having an inhouse writing team helped give the characters a consistent voice, even if we didn't like that voice. It also allowed the characters to have actual arcs and growth (if you haven't already and have a ton of time to spare, I encourage you to take a look at this reddit post (or the HotC article that it eventually became) about Jace's growth up to Ixalan). Then we moved to established authors for reasons that I don't think were ever explained and in the very first outing (Dominaria), all of Jace's growth is thrown out in one scene (and he's not the only victim of this). Then you have outside authors being allowed to make large decisions for the story based on their vision of the story. No offence meant to Kate Elliot, but I believe it was her idea to make Bolas and Ugin brothers. Just because it was her idea doesn't mean that Creative had to say yes. But they did. Same thing with Weisman and Dack Fayden. I don't think I would mind these changes as much with 1) more communication from Creative and 2)a stronger separation "between periods". Not being able to keep continuity consistent within the same arc (Kaladesh to WotS) is incredibly frustrating.

Your point 2 is an interesting one to me, because it reminds me of the original Revision and the Mending. Both those time, there was a major and transparent change, and both times we launched into something honestly NEW (the Weatherlight Saga or 100 or so 60 years later when all the previous characters should have already lived out their lives were mostly still kicking.)

And yeah Jace on Ixalan was pretty good.