I sort of see where you're going, but you're also missing a few pieces of context, I think.
1) He's also taken over a fairly major chunk of Hell itself, and decided to split some of it off to create his own private realm
2) Where, in said realm, he's been assembling and dilligently training up what appears to be a pretty significant army.
3) He's exploited Freyja's mental fault lines to the point where, I suspect, she'd probably be willing to side with him over Asgard when that eventually comes to blows.
4) Rather brutally damaged Raven, and gave a pretty good accounting of himself against Gryphon in the process.
5) Has (as of the Diqiu suite) inserted moles into DSM, where he's likely to be sowing some seeds of unrest and / or siphoning off more potential candidates for item 2.
6) Made it pretty clear in some of the OOTR asides that most of your points about being caught out (or deliberately showing his hand, ie: the wedding) were intentional moves to make the Trinity and their various allies think of him as a paper tiger.
In addition to being a predator, it's worth pointing out that Akio has been, in canon and his UF appearances, an incredibly nasty and effective manipulator, and it looks to me like he's spent a lot of time and effort to misdirect his enemies, while preparing what I suspect is going to be a VERY nasty sucker punch.
About the only hole card the good guys have right now (as far as we, the audience knows) is that Saionji, Mia, and Anakin are gathering a fair bit of intel from the inside, and that Akio doesn't know they're double-agents.
But it also wouldn't shock me if Akio knows a lot more than they think (see point 6) and has something nasty in mind for them as well.
I see Akio as the complete opposite of a moustache twirler - he's a chessmaster, and he's not afraid to make himself look foolish for the early portion of the game if it helps him set up his endgame.
Matt "BZArcher" Wagner
@BZArcher / bzarcher at gmail
"Here's an itemized list of 30
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