My best mic for my vocals is one that is anything but neutral. Really weird frequency response. It’s the MXL 4000.
Well, that is not the case here. Among a bunch of other mics I have the Blue Bottle kit with all available capsules - and also a custom made CT-12 (Tim Campbell). And even though I usually will start out with one of 2-3 capsules, I tend to try with all capsules - and the experience just tells me, that I can record four songs, with MY own voice, and find four different capsules suitable for the four tracks separately. The one that works wonders on one song, will be useless on another - and vice versa.
I am a firm believer the following terms should be erased from existence; "Best microphone for this and that voice", "Best microphone for soprano/barytone/etc. voice" and so forth... It has been said OVER and OVER and OVER again. Everyone can give their opinion - no one but you will know yours.
There are some things that will
most likely work on some things (like a Royer R121 on a guitar cab) and some mics that will
usually yield a good result (like an U87 on vocals) - but not always. Sometimes a U87 will enhance unwanted frequencies in the room, the timbre of the voice in that particular track, or just make the vocal performance unable to sit comfortably in the particular mix. Sometimes a SM57 will do a better job in that application. Or an SM7B, or an M49b, or a C12, or the crappy mic in your handheld cassette tape recorder - or a NT1a(black - whatever)... I just have to say, about the latter mentioned Røde mic, it has not happened to me. I have a couple of mics I do believe will NEVER get a position in anything I do. NT1 is one of these mics, and probably the worst on the list too, along with AKG C1000, AKG C3000 and sE Z5600.
I do believe, that if you do multitrack recordings - say vocals, backing vocals, acoustic guitars, percussion, and whatnot - and only have one microphone to perform the task - you will get the most neutral and workable result with any linear microphone that, most important of all, delivers a realistic transient response. Get as good info "on tape" as even possible, would be my mantra. Colouration is good, but it is just so difficult to remove colouration once it's added "on tape" - and very easy to add come the mix process.
Another thing with mics that add colouration in form of distortion and uneven frequency response is, that all the tracks will have the same bumps and grinds, since it has been recorded through the same microphone. It's like if you're a painter. It is so much easier to see what you do, if you are wearing non-coloured glasses as opposed to green glasses.
Bottom line to the OP is, that I do find coloured mics to be good for a lot of things, but if you have a limited amount of mics, I really suggest you use the least colouring mics available to you.