What's the best saga of DBS? Black, easily. What DBS needed was more good ("good") villains, that simple (or tough) I think. Jiren's too little too late, the tournaments are cool but the DB tournaments actually had two villains that both had engaging backstories and became two of the most beloved characters of the franchize. DBZ had less interesting villains, but they were chronologically: Z's Piccolo and a saiyan rival to goku, *the* tyrant evil dude of the franchize leading goku to his most iconic moment, the culmination of the red ribbon army that emphasized the next generation AND the idea that there's something even beyond a ssj, and finally, basically, DB heaven and hell edition.
As much as DBZ gets crap, overall, that's a good progression of main events. If Buu was centred around evil, and hell attacking heaven, Black was centred around heaven's corruption itself, and reaching beyond timelines. And that's about it. Super offered nothing else truly. There's no true real new villain concepts and situations. If there's one it was Hit, which imo they should've expanded upon before even thinking of going into even more massive power-ups and transformations.
Super should've had a Universe 6 saga, and Hit having more backstory and actually needing Goku's help against some insane lunatic. Hit was seen in urban areas there, it could've been something a little more intricate with Goku having to also protect people for once instead of fighting in empty areas.
That's my take/idea on it. DBS was surprisingly fun to watch but ultimately hollow and added nothing new except the idea of a God gone rogue and a few moments we fantasized about as fans after Z. And it definitely could have, as I said I define the central problem as lacking good, clear villains/antagonists and new situations in which to deal with them.
Absolutely love that theme music. 
