You care about Bazz-B because he is not that bland as majority of Sternritters (tho he is still not to be compared with non-Quincies). Flaschback can help his character, get more deeper, and I hope it will not just be 5-10 pages like As Nodt had. One more thing is that Bazz-B has great design, even compared to other Sternritters, which designs were good.
Hashwalth is ruler while Yhwach is asleep that was pointed 50 chapters ago, in chat Hashwalth and Uryuu had. For now Hashwalth is just Grandmaster, and when night comes his powers will change to Emperor level (something similar Askin pointed out during Hashwalth and Bazz-B's talk). But, even it's just Grandmaster Hashwalth, it's still impressive that Bazz-B is fighting like that against Hashwalth. Grandmaster is title higher than Shutzstaffel and Bazz-B is below it. Plus, Hashwalth still seems to be higher than Uryuu, that's considering title (Uryuu is prince, but it seems he is part of the SS as well) and strength, not to forget that Uryuu sent Ichigo flying. Someone would probably say I am mad for comparing Bazz-B to Ichigo in strength, but when Bazz-B attacked Ichigo in that 8 vs 1 fight, it wasn't Ichigo who stopped Bazz-B (like he did to other SR), but someone other. (can't remember was it Rukia, Byakuya or Renji atm).
Also when we are talking about Bazz-B's powers, it's pointed out by Hashwalth that wound he got is from Aushwalen which mean Renji and Rukia, together couldn't do much to Bazz-B. And one more thing, Bazz-B said that SR who were hit by Aushwalen are dead, while other who escaped light, just lost their Vollstandigs, it's weird considering Bazz-B was hit by Aushwalen and is nearly as good as new.