>>3295888>developed and scanned in the lab.some people get great results out of their local labs' scans, but that seems to be the obvious culprit if you're unhappy. yashica's should be able to pump out plenty of detail in 120.
if you have another lab nearby it could be worth a try to see if they handle your shit better, otherwise you're going to be at a fork in the road where you either decide to scan yourself and figure out that workflow, or give it up.
pic is from my fuji 645, i'm pretty happy with what I've been pumping out of a pretty bottom tier flatbed.