As Lss pointed out, the 35/1.4 has focus shift, which IMO, can also be a problem on film and may be a reason some of your film images have incorrect focus.
Lenses with focus shift typically cause the focus to progressively move farther back behind the intended point of focus as the lens is stopped down, until the point where depth of field is deep enough to mask the effect. It also seems to be more noticeable at nearer distances.
Rangefinder lenses when used on a rangefinder camera seem to come adjusted for focus shift in two ways:
1) correct focus and rangefinder coincidence wide open. As the lens is stopped down, the focus shifts increasingly farther behind the intended point of focus.
2) correct focus and rangefinder coincidence at about two stops down. This is like a compromise setting that aims to minimize focus shift at all wide aperture settings, but the consequence is that images shot wide open will be slightly front focused if rangefinder coincidence is correct, but the backwards focus shift at somewhat stopped down apertures will be more quickly masked by depth of field.
With respect to the 35/1.4 on the Sony camera... if you focus then change the aperture setting, there is a chance you will run into focus shift problems. If you use focus peaking at medium to far distances at middle aperture values, you can end up with a scene swimming in focus peaking artifacts, leading to believe focus is good anywhere, but then later learn when looking at the full-rez images that it wasn't the case. Precise focus with the Sony cameras can only be assured by magnifying the viewfinder image while focusing. This is good for static scenes, but can be difficult for any dynamic situation.
The 35/1.4 is modeled after the original Leica 35/1.4 from around the 1960s and as such is intended to mimic 'vintage' lens performance. That means it's not super, highly corrected like pretty much any modern lens design. Take for example the new Voigtlander 35/1.7, which is bitingly sharp with very good contrast (though exhibits significant field curvature on Sony cameras). On digital it's easier to zoom into the aberrations of the 35/1.4 that otherwise blend in and add to the various aesthetics of film images.
Quickly looking at the photos you posted on Flickr and my impression is you need more practice focusing. It might be helpful if you outline your shooting/focusing technique with the Sony camera in greater detail.
You've gone from a Canon camera with which you probably relied 100% on AF for focus, to a mish-mash combination of a quirkily lens on a camera it wasn't originally designed for, forcing the use of manual focus and more careful technique. In some ways the two are at opposite ends of the spectrum. As a result, there's going to be a learning curve involved.
If you're looking to add more lenses to both system, I would suggest something like the Zeiss ZM 50/2 Planar. It's a good all-rounder without any peculiar quirks that works well on both rangefinder and mirrorless systems. Pretty much any 50/2 out there should be similar (other than maybe the Leica 50/2 APO ASPH) and might be a smoother combination with the Sony to get up to speed. With rangefinder lenses wider than 35mm you start to run into a range of considerable technical problems related to how the Sony sensors are designed vs. how the wide angle lenses were designed originally for film use (or Leica-specific digital sensors). Rangefinder lenses longer than 50mm generally have no technical loss in performance on Sony mirrorless cameras.