This is a tricky one, and it's very true what Bentley said so far we haven't seen an upper limit to Death Sentry as of yet.
DS Sentry is most likely stronger and more powerful than both Void and Voidtry.
Like I have mentioned before he doesn't have his Agoraphobia so he isn't afraid of saying f**k it, I am bringing my A game here. And this Sentry isn't exactly devoid (is that the right term?) of feats.
He's not exactly a slouch when it comes to speed. And he has a killer punch on him. And when you consider that for the 2 times he fought Thor he was holding back on every punch and he treated him like a baby.
it's hard to peg down where Sentry fits in a tier list. I mean it's a given that he is a solid Trans Tier and given he is probably more powerful than Void, I can see this being tough.