I've had an A6000 since early 2019. I love it. In the last year I've acquired 5 lenses.

Sony 55-210mm
All 3 Sigma Prime Trios
7Artisans 50mm f//0.95
and of course the 16-50mm kit lens.

Basically the 7A is for black and white portraits, the Sigma 56 is for color portraits, the Sigma 30mm is my walk around lens, the 16mm is my landscapes and astrophotography, the telephoto is obvious (I love this one way more than I expected) and the 16-50 only gets used for video occasionally because of the OSS.

I want a travel ready kit. I've been thinking about getting the Sigma 18-50mm F2.8, the Sony 11mm f1.8 and pairing those with my telephoto to be my travel kit. I've also wanted to sell the A6000 and buy a used A6400, for the picture profiles (flat, for video color grading), eye autofocus because sometimes at f1.4 my portraits aren't focused right (a convenience thing), and for 4k video. Even though the A6400 doesn't have IBIS, it sits in a price sweet spot where I see the value for the features it has. I don't see that for the A6600.

The cheapest used A6400 I've found locally is $999 CAD.

I have found a used A7ii for $1,100 CAD and it comes with an extra battery and the 28-70mm lens. For almost the same price, I can have IBIS and a FF OSS lens. The A6000 doesn't have anything the A7ii doesn't. People complain about the A7ii battery, but it lasts as long as the A6000.

I won't have 4k video or the picture profiles though.

The A7iii would be like $1,650 CAD for the body only.

What would be the better choice here?