I've been keeping up with the series weekly through the good and bad since it aired. I had mixed feelings about the end of the arc, too, but I think I've come around to it after some thought.
The Vegito ending was heavily foreshadowed both in the appearance of both Supreme Kai, Zamasu's own fusion, and episode 65's own fucking preview. When it actually came time for the fusion to happen... it was just rushed. Vegita uncharacteristically gave in quickly, the flashing lights and fusion ended quickly, and Vegito's introduction was just there. The whole pacing for the Zamasu vs. Vegito fight was so rushed that, looking back, I think it's obvious that this was meant to be a sucker punch in terms of how the fight was going to end. The Final Kamehameha was executed and, because Vegito abandoned his ki preservation in an attempt to finish the battle, it surprisingly ends up messing up their chances of winning not just for the present Zamasu fight, but for the one after Zamasu's infinite power is forced to abandon its physical form and take on a new objective. Trunks ending the battle is fitting and, in theory, this whole thing should have flowed really well and concluded nicely.
Unfortunately, I think it kinda fell flat from the perspective of the animation and art direction. The emphasis on animation during the Vegito v Zamasu fight is obvious, but other than that I can't help but feel they really dropped the ball here again. I'll give an example in the form of the final blow from Trunks' Spirit Bomb Sword
You aren't seen something like Cell being overwhelmed by the ferocity of a finishing Kamehameha and his body being literally obliterated into nothing. You aren't seen something like Kid Buu struggling desperately to make that final push and overcome Goku's last remaining hope in the Super Spirit Bomb only to fail and be similarly obliterated. No, instead, Super goes with the controversial move of having Trunks stand motionless with his blade, the most important part of the fight, out of frame as Zamasu's death takes up maybe a little more than half of the screen with really little to no pushback since he had kicked down Vegita and Goku. Also, it baffles me that they wanted to end the episode with this exact frame --
They choose to show this Zamasu form's defeat in the most stunningly disappointing fashion possible. To me, it felt as if Trunks battling Mecha Frieza, a fight that's animation direction was tailored specifically to show off how strong Trunks was in comparison to Mecha Frieza, was more of a hassle than Trunks vs Zamasu. You saw Trunks' explosive power in the final attack on Mecha Frieza, easily reducing him to nothing. Here, you get a clean cut and awkward holding of poses. If you're going to introduce stuff in an episode that many viewers would consider world-shattering events (potaro rules being affected, trunks being inexplicably stronger than what you'd expect, and spirit sword stuff) then you cannot just disappoint by showing direction like this. Fans will be far more inclined to just leave the series and write off plot points as lazy if the art direction isn't executed perfectly.
For what it started out as, Super has shown an astonishing rise in quality and I'm excited for more episodes. The ending was a little off-putting, but the ride with Zamasu was extremely enjoyable, built the world even more, showcased character growth (Vegita changing his battle stance in the final battle against Black to incorporate Whis's suggestion of loosening up was a really nice touch), and it had a genuinely interesting and engaging ride up until those final moments. A lot of the battles really showed a level of quality I could say rivaled, if not beat out, a lot of the best moments in Z. They just have a few more edges they need to buff out.