The song overall is a well constructed and interesting tune, there are no points were it sounds "thrown together" as a song. I like the way that each section is slightly different on repeat and the song has a feeling throughout that it's building up to something and is seriously catchy. My only major criticism is the use of what sounds suspiciously like a drum machine on the choruses and it drops a lot of bottom end out of the mix, however, in these sections, the snare has a bit more snap which might work well on the rest of the tune, speak to your drummer!
I also noticed the vocal tuning "problems" but in this song it doesn't sound like a problem, the vocals in Gang of Four, The Stranglers or ACR weren't perfect either but they work.
As a guitarist myself I'm not sure about the short solo but it would come off much better and add to the song more, with an effect, like a wah-wah, a bit of delay or something whackier like an electro-harmonix micro-synth perhaps.
My advice to High Horse is get off your high horse.