I have two J-8s -- one is OK, the other a little better than that. The better one can give "modern" results, but it remains a sonnar design which I always think of as a "vintage" type lens. Maybe not? I have the Contax/Kiev version (J-8M) and its definitely a better performer on film than my other J-8s (I have no way to try it on digital). For the price, and with some careful shopping, could fit the requirements.
I have only one I-61LD now. The lens is capapble of sharp-ish modern look, but its the cheapest build RF lens I own, hands down. Barely usable. I simply don't use it.
I have a few I-22/I-10/Fed-50 lenses. I consider them quite good for what they are, but they're slow and seem to be "vintage" in my eyes. Perhaps its the low contrast?
Canon 50/1.8 and 1.4 are good for me. I have both and rather like the 1.4, but I need to shim it for the Leicas. When I have time...
The Nikon LTM lenses are very good and fit the requirements in OP. Either the f/2 or the f/1.4 will work (though I don't have the f/1.4). I think these are also sonnars. But, contrary to my earlier statement above, somehow the images don't look that vintage to me, but rather modern.
I don't have the 7A or a color skopar (in 50mm). Can't comment on those, but I'm awful tempted by the 7A.
You have a very good J-3 Kostya. So I know you have the sonnar look covered.