Bliss goes to +12 so there's 17 steps of headroom generally speaking, but the steps are not exactly linear. I was listening to some music for example tonight, at -30 was a bit too quiet for the recording, turned it up by 5 steps (to -25, could have been fine by just -2 or -3, I just like jumps of 5) and it felt like 10dB at least.
I haven't tried a Susvara on my system but I've read peoples impressions on the Susvara in the past, some were saying they have it on -15 for example or even I think someone was running it at like -30 as well and people were shocked at the persons sensitivity to sound.
But then again, it depends on recording as well, to me it seems we're dropping off the loudness wars because so much content now is much quieter and I have to crank it up more.
Well anyhow, I could always upgrade in the future, obviously, Bliss is not the most powerful, and I also still have the Volot which has 16W of power and a TON of gain