I don't think you can really mimick that look you are missing with digital.
I was really really tempted to go digital, but in the end I decided to stay with my
Mamiya Universal, and now I'm going to sell it to get a tech camera with a 6*9 back ....
Archiving was one reason, but the other was exactly that "look".
I have made some images I really like with my small p/s camera, which kinda is a
paradigm for the digital look (small sensor, sharpness behavior),
but somehow I really hate it..
If I'd go for a semi-affordable digital system which would be similar to what you are seeking for,
I'd try to get FF and very fast excellent lenses, like 85 mm F1.4, 50 mm F1.2 and the like.
Leica M with Leica or Zeiss lenses or Canikon + Zeiss lenses ...
A pro photographer recently told me he regretted selling a Canon 50 mm F1.0, which made images
"explode" (as he told it), and that he hoped to get one back used ....