I'm with you on these points, his enhanced speed/reflexes, the durability to survive (albeit barely) attacks that'd be lethal to a human and his ruthlessness are his main advantages. He also has a strength advantage over May and Carter.
I'm not with you on these ones though. Blonsky's roughly level with May as a marksman, ahead of Carter. In hand to hand/with melee weapons, he's shown no skill whereas May's on Black Widow's level, M'Baku's skilled enough to take on depowered Black Panther (a world class martial artist) and even Carter's shown some skill.
I agree weapons make a difference. Blonsky's best chance is in a gun fight but he'd be one expert marksman up against another expert marksman (May) backed up by a capable one (May) and a close range threat (M'Baku). If they end up in close quarters I think he gets outskilled and overwhelmed.
This is going to be an agree to disagree situation.
As for skill in hand to hand, I think it's a reasonable assumption that as a special forces soldier ( Royal Marine Commando) Blonsky is capable of holding his own in a fist fight with Carter and with the super soldier serum, May and M'Baku as well. He's also going to be significantly quicker than any of them, andwe know he's much tougher than an ordinary human ( stronger ? unclear if he's stronger than M'Baku, but he's faster).
Their best chance is to rush him all at once and pin him down.
I'm not really an agents of Shield fan, so how often do we see May fighting to kill an opponent or beat someone to death with her bare hands ? I found a few examples on the Marvel fandom wiki. Is she really meant to be as skillful as Natasha ? The fact that she has "more black belts than the Black Widow" doesn't mean a lot, given that it was Widow's job to murder people.
In both TWS and CW Nat shows impressive hand to hand skills and marksmanship ( against human opponents) particularly in the Lemurian Star and Lagos sequences - and she kills without hesitation or even changing her expression.
Is May really as good or as deadly ? Again, I don't have the AOS background to form an informed view, but I'm skeptical - again, given that Widow used to assassinate people for the KGB and has shown herself capable of taking out /killling multiple opponents including mercenaries and Strike commandos...so I'm sure May is very skilfull but I'm skeptical that she is on Nat's level. Please correct me if I'm wrong.
There's a vs thread idea!
May vs Black Widow.
I note that even Widow was clearly outmatched by Bucky, her multiple downward elbow strikes to his head ( which would have likely stunned a normal human) had no effect on him at all. How would that compare to Blonsky vs May, unclear but I highly doubt she'd be able to take him down one on one.
M'Baku fights BP as a normal human and with weapons, but honestly he stays in that fight due to his superior strength more than anything else- he gets taken out with a variation on the triangle choke ( BP relying on skill). I think in a hand to hand or weapons fight he could probably beat non super soldier Blonsky one on one - but Blonsky with the serum is a different story.
Carter, I don't rate all that highly as a marksman or a hand to hand fighter - she wasn't able to shoot Rumlow during the TWS firefight and if she thought she was going to take out Bucky with head high kicks, she was dreaming - which is why she gets dumped quickly ( and she was wrong when she told Cap that Bucky had tried to kill her, he was only trying to escape at that time, if he'd wanted her dead she would have been). If this was Maria Hill, rather than Carter, I might have voted differently as she's demonstrably a better shot and much sneakier than Carter.
IMO, given what we saw in CW In a hand to hand fight Carter and team vs Blonsky, Carter goes down first after a single hit - TBH what she showed in CW wasn't all that impressive.
May may be skillful but given Blonsky's enhanced reflexes, sooner or later he lands a solid blow and she's done - and we know that he's tough enough to absorb her best shots. That leaves M'Baku, maybe he's able to choke out Blonsky but strong and skillful as he is, he's still just human.
With melee weapons ? M'Baku is pretty deadly with his club, that might be enough, but again with Blonsky's speed advantage and a knife ? Maybe not enough after all. Blonsky could likely ignore all but fatal stab wounds from Carter and May, but could disable them very quickly.
Guns, and this is over real quick. With Blonsky's enhanced reflexes he gets the draw on May and 3 headshots later her team are all down.
I still think people are underestimating the advantage of Blonsky's ruthlessness. Things that May, Carter and M'Baku would need to be desperate to do Blonsky would do as an opening move - he'd slit their throats without hesitation.
That's how I see this playing out. If this was Blonsky vs Black Widow, Maria Hill and M'Baku I'd give it to the team- because both Hill and Widow are also ruthless killers. I don't know enough about May ( and would be surprised to think she's up to Natasha's level) and Carter really isn't anything special.
IMO M'Baku, Okoye and Shuri would win this one too.