Regarding picture quality, everything you describe is normal for a non-1-chip SNES. It’s simply down to the blurry rgb output (you can read about that phenomenon here: http://www.chrismcovell.com/gotRGB/snesblur.html .
For generic 4:3, I’ve found scanlines to help quite a bit. By the way, I also have slight jitter in the horizontal direction, but it is not visible at normal viewing distance (modded PAL console with 59.53Hz output). I have a 1-chip, but it is being repaired, so I cannot confirm if this removes jitter in this case.
You will not be able to get an acceptable image in optimized mode, unless you also use the new deblur (“reverse LPF”) feature of the 0.79 firmware. However, the results will also vary with particular console, because some are more blurry than others (I had one where it worked nicely, another where the image could not be improved without artefacts appearing). And from the looks of the images, yours seems to have quite severe blurring, so don’t expect too much from that feature…
I suspect your image drops would be improved by using a proper NTSC console, or a SuperCIC moded 1-chip PAL.