I've decided to update this a little, time-permitting, with a number of the notes y'all have given me. I did want to point out a few things that may in-fact be tricking your ears:
Gario:
I checked and both the bends AND the landings are slightly off on the lead guitar for that first melody runthrough. However, funny thing, is that same run is copy/pasted for the second and third time later in the song. Funny how you said that the second sounded on because of the accompaniment. I am curious as to if the accompaniment's notes make it seem more on-point.
The synth-tar lead for the 1:16 section is the same volume throughout, but what might be throwing you off is something that's not as apparent: there's two synths playing the same thing. The more apparent one is a single lead with a bit of distortion and warble. The BACKING of it is a phased and delayed lead with some really cool latency (you can hear part of the effect right after all the instruments cut out after that section, listen in your right ear and you'll hear the delay being phased and faded out and then slightly faded back in). It's a dynamic phase so each time it's exported it is usually rendered differently. That track is frozen, though, so I can try to automate the volume on the first part to be slightly lower than during the second part, where you said it sounded better.
Shade: That off-beat snare hits might be exhibiting that because they're not quantized. I don't think the volume of the hits will make much of a difference, but I'll try it out. That particular beat was from a Groove Monkee midi pak, which they ship unquantized to have it seem more human. I'll see what kind of tweaking is needed to stop the jerky-syndrome you're experiencing.
and just in-general stuff:
The parallel 5ths stay.
I'll do my best to clean up the production where I can. I'd say this is 97% done to my satisfaction with production, and usually whenever I'm mixing, I will settle for things above 90% in my weaker areas such as production and drums (this is to combat my perfectionist tendencies and have it so that I do FINISH mixed instead of infinitely trying to improve them). So if nothing else can be done to improve it on my end, I'll keep it as-is. BUT, like I said, I will try.
I'm going to try recalling my sub and sending in this one ASAP, so it might be updated before you know it.