It's just so subjective, one has to be so careful when choosing a lens with "character". And it's lenses which can really get you deep in. So many issues arise. Differentiating "dreamy" and "not very good" has been a bit of a challenge for me, ie pre asph Summilux 35mm which, used, still commands the price of a couple of FF cameras. Anyone heard of 'Mandler' lenses? If not, that's probably a good thing for your wallet. I have one of 'em and slowly but surely will add to it over the coming years. It's bit ridiculous when you have a camera and Zeiss lenses are not 'the one'.
Well, it's super easy to find lenses with great "character" these days - if you're ready to experiment a bit and forego prejudice. The Voigtländer 35mm f/1.4 Nokton Classic (especially the first version that I own) has tons of what goes for "character" - it has glow, it has focus shift, it has swirly bokeh, it has harsh bokeh, it has all abberations in spades ... and it's still a lens you can take very appealing images with! And the 7Artisans 35mm f/2 is an astonishingly good lens with just minor weaknesses at half the price of the Nokton Classic - it's almost on par with the current offerings from the established boys, Leica (Summicron ASPH - ten times the price), Zeiss (Biogon - three times the price) and Voigtländer (Ultron Classic - twice the price), and it sure renders beautifully. Bottomline, as long as you crave the big names, let alone the legends (that are sometimes just vintage - i.e. technically less advanced than modern designs), you pay the price.
Unfortunately, if you want a modern RF body, Leica is your only choice, but I think we've discussed this extensively ...
However, not so with lenses! You just have to experiment and be cautious not to fall for any kind of hype. A couple of my favourite lenses are made by Zeiss (35mm Biogon C and Distagon - both smashing performers in their own right!) and Voigtländer (the new 50mm f/1.2 Nokton, my most rewarding 50mm lens - notice that I don't say "best" ...). Admittedly, neither of these lenses is what you'd call cheap in today's market. Leica? Fantastically reliable lenses, all of them, but none of them makes me want to shoot them constantly the way the aforementioned lenses do. The Biogon C is so good that I actually hesitate before taking it off the camera - and the Distagon is even better, though its size and weight prevent it from being the "one and only".
Of course, true Mandler designs will perform better than the Voigtländer Nokton Classic, but they come at ludicrous prices nowadays, especially the early ones - $14,000 for a 35mm f/2, anyone? Yes, that's fourteen thousand - and that's after a $1,000 price drop! You'd have to pay that much for a Summicron 35mm f/2 version 1, the "true Mandler", around here.
On the other hand, the lens I have the most fun with at the moment is the 7Artisans 35mm f/1.2 for APS-C (on a lowly Sony A6000 in my case) - it's a bit more expensive in Europe than it is in the States, but it's still very cheap, and it's really quite a solid lens with, yes, lots of "character". Objectively speaking, this throw-away lens is no worse than the venerated (by some) Voigtländer 35mm Nokton Classic (except for the huge flare), which in turn is only marginally worse (the focus shift ...) than the first and second versions of the Leica Summilux - Mandlers design you pay top dollar for, as
@rayvonn said. Would you take a $14'000 lens out to shoot? What about a <$150 lens (new!)?
When it comes to lenses, there's more myth and hype around than is good for your health. The sensible thing to do would be to find something that satisfies your needs and stick with it. Buy used if you're uncertain. Even so, if you love collecting and have the resources, by all means, go ahead.
For my part, I'll freely admit that I now prefer experimenting over "holy grail" purchases. My own obsession with 35mm lenses has landed me with six for M mount: three by Voigtländer, two by Zeiss, one by 7Artisans. Still, I didn't pay as much as one single Summilux 35mm FLE would cost new (or even used, come to think of it!) for the lot. And I'm pretty sure that at least the Distagon is at least on par when it comes to optical performance ... so, it may well be that I got a "holy grail" lens in the process, anyway.
But you know what: The lowly 7Artisans 35mm f/2 is even more fun to shoot with on the M10 than *either* of my two "big gun" Zeiss lenses. Food for thought.
M.