They did the same thing with Clone Wars, after the first two seasons all the main characters eventually got a full overhaul. Apparently this is partly for technical reasons as they improve the animation rig they pretty much need to periodically rebuild the hero models anyway. Another part is I'm sure to do with toy sales, but since that's what pays for the show and it works organically, I'm fine with it.
As for Ezra, I don't think his change is any more dramatic than Ahsoka's when she went from 14 to 16 mid-way through TCW. It's always going to seem sudden when they switch things up because these are characters that have to be built, not actors who will grown and change of their own accord. One imagines it would be unfeasible to slightly alter a character's appearances every episode or so to simulate natural growth, so we just have to squint and pretend it's more or less seamless.
I wish they'd update Hondo's look. He looked so much better in Clone Wars.
I think that's the point though. During the Clone Wars he was a pirate king and war profiteer, but now under the Empire he's been reduced to a washed up, two-bit conman. All he has left are his wits, charm and greed.
The Clone Wars version of Hondo is certainly cooler, but I like that they evolved his character in an interesting way that makes sense. One imagines after the War the Empire cracked down hard on organised criminal groups like the Pykes, Black Sun and maybe to a degree the Hutts. The latter I suspect cut a deal with the Empire that allows them to operate on the outer rim without interference in exchange for some form of tribute.
It would stop the fringe worlds from banding together and ensures the Hutts with police their own territory, preventing any other groups gaining undue power.