lmao...dude, you're nice to say that, but like most of us, I'm a home hacker with shitty gear. The vox on the one you listened to were tracked with a piece of shit AKGC3000 (I hear it's good on drum toms, but it sucks on vocals). You can hear the problem mostly on consonants...my "s's" peel your eyebrows off, lol.
What I mean by "dark" is that muffled sound you're hearing...I didn't hear it on headphones, but I did on monitors. It's your mic. I can say that because I have one of those 990's. I probably got mine when you did...when they were practically giving them away from musicians' friend around christmas, lol. It sounds to me like it's a "scooped" mic, meaning that the stuff between 1K and 3K is kinda' missing, and the stuff over 5K is hyped. I haven't looked at any graphs or anything, but that's what my ears tell me. I've only used it on one tune, and it just sounds "darker/duller" than other stuff.
Nothing for you to be embarrassed about in this tune at all...it's in the working stages, but I've played it several times...which is several more times than most tunes I pick up on the net. Please finish it, because there's something about it that makes you wanna' listen. When you're done tracking the vocal, maybe boost it a touch centered at 2K about .5Q wide ... up maybe 2 or 3 db right there and see if it gets a bit clearer...watch that the top end doesn't get TOO bright when you do it tho.