It's clear from their lens pictures that aperture blades don't open fully. It doesn't mean all lenses will be like that. Just typical sample variation and unfortunately it happens with different manufacturers more often than we would like. If that's very important to you, return and get a different copy because that is considered "within specs" even by Zeiss.
Unfortunately, you can't expect really low variation from such inexpensive lenses. Higher level of quality control will quickly push the price to 5k USD like Otus or even higher. Just look at strickly manufactured Cinema lenses, for example, ARRI master primes at 25k a piece. Or supertelephoto lenses like 400/2.8
I'm also afraid that with recently increased IQ standards for all FF lenses it's inevitable that manufacturers will use more complex designs. Have a look at new Sigma 40/1.4 that weighs 1200g.
Performance wise this 40/2 is very close to 85/1.8 batis which in my book is exceptional, and it even beats 85mm in resolution uniformity (albeit very very slightly) and in level of correction of loCA which is exceptional for a fast wide angle lens. I didn't expect less with 7 out 9 elements being either ED or aspherical or both.
Batis lenses have excessive diameter, and I obviously don't like it. But they are compact and lightweight. I think the smallest we could possibly expect is Nikon 35/1.8 S, but it's just a bit narrower and still as long and heavy.
