BLack Panther should be top tier, he's stalemated cap many times, and owned karnak, he's stalemated daredevil as well, ironfist too...most of his appearances point to him being their equal in terms of H2H
Or, like, a dozen of the best lackies he could hire in addition to himself, or he made advanced combat scenarios tailored to her.
With his keen mind, I could see him being a smart teacher who was able to teach a student to surpass him, which happens occasionally. David Cain taught Cassandra to be better than he was after all.
Thanos doesn't need to be as good to teach her to be as good as she is.
Very good point about David Cain the featless "greatest assassin in the world" training Cassandra Cain. It was probably something like that. Thanos may lack the agility and speed to pull off a lot of the techniques he knows but he can still pass down the knowledge to someone who can.
__________________
“Where the longleaf pines are whispering
to him who loved them so.
Where the faint murmurs now dwindling
echo o’er tide and shore."
-A Grave Epitaph in Santa Rosa County, Florida; I wish I could remember the man's name.
Try to bring order to chaos, and it bites the hand that feeds. Oh well, I'll play.
BattleHammer, Philsophia, Kris Blaze, jinzin, Nataku, V, Soljer, marvelprince, iceman24567 and I vote for Punisher to be in the third tier.
Alternatively I think Colossus, Thing, Superman, Wonder Woman, Strong Guy, Thor, BRB, She-Hulk should all be in the now unrestricted top tier. Because they would beat the crap out of or "do very well" against everyone currently in the top tier in "h2h."