You asked for honest critique, I will deliver.
First, off, this is totally a personal thing, I don't really like your vibrato. Too slow and pulsing for my taste. But if you like it, keep it. Other people here seem to like it. Maybe keep it the way it is on the high notes, it sounds much better up there. And then work on speeding it up down in the 3rd octave, where it tends to get too extreme. But again, only if you want to. It's totally a matter of personal taste.
Nice harmonies, works well with this song. You could be a little more precise with them, in terms of the rhythm and making sure they follow the melody a little more, if you understand what I mean...try to keep more consistent intervals. Map them out beforehand. It sounds like you were kind of ad libbing them here.
around 2:00...do the "confined", all the F4's in fact, throughout the whole song, in chest voice.
Love the little timing difference on "higher". Rob does it on the offbeat and you do it on the onbeat I think...I like your way better. Works well with the way you kick in the vibrato on the second syllable.
around 3:07...again the phrase is too heady, though this time I think the biggest problem was the A4's were not dampened enough.
the "abide" C#5 could use a teeny bit more girth. Put your whole body into it, blow the air hard, let it distort a bit maybe. Also, maybe get rid of the "ee" diphthong at the end and just say "abahd". I think something about that ee at the end left it off with a girly/operatic vibe that wasn't present during the note. During the note you sounded pretty cool.
Very nice riffy "yeah" in the bridge.
On the end riff of the bridge you twanged too hard on the B4. Of course I'm nitpicking at this point.
On the outro when you first phrase you start going high, I liked the last C#5 but I stuff before I thought was too light and overtwanged.
I would recommend you own up to your baritone range and stick to the original melody there, and maybe just throw in high notes as accents. I think that's more what your voice is meant to do. It's a hard thing for us to accept, I'm a baritone too, but it's what the audience wants, it's not just about the notes you pick musically, it's also very important to tailor the melody to the individual characteristics of your voice. Baritones can sing great high notes here and there, but when we try to sing whole phrases really high, we tend to not do it as well and it breaks the illusion of maintaing full voice. With loads of training it can be done but you're not at that level yet, neither am I, most of us aren't. Singing with good mass and natural enunciation around the A4-D5 range is a really freakin hard thing for a baritone to do. So, my philosophy with that is, train the hell out of it, but in the performing art known as singing, don't do it unless you really have to.
On the high phrases after the key change, again, right around Bb4 and B4 you are overtwanging and not dampening enough.
Keith, the biggest thing I'd recommend training right now is wind & release and dampen & release onsets on A4, Bb4, B4, maybe C5 (there aren't any C5's in this song but if you hear the same quality in that note include that too), and focus on rebalancing your tone to something darker. You have more than enough twang, so just forget about it, erase it from the mind. Put your focus on lowering the larynx, maybe a little more jaw drop too, and work on the vowels "uh" and "aw" up there.