NOT a rant...because I can (barely) see this entire post without scrolling... 
I've been playing tubas, now, for over a half century, and never took a break from it.
I like doing it a whole lot, but I've never felt it was a "calling".
When I was first paid to play the tuba, my eyebrows were elevated, because (even though much easier than playing the guitar) playing the tuba paid more than playing the guitar...which (playing the guitar) paid considerably more than working at an Exxon car wash 24 hours each weekend...
...so - though "playing music" is not something that is required for human survival (such as supplying food/shelter/clothing/heat/transportation), as long as it paid more - and was easier - than did some essential-to-human-survival jobs (though that probably is no longer true), I've been on board. (We all look up to people who put in the time/dedication to master musical performance to pinnacle levels, but all that work was still far more
comfortable that climbing around in a fiberglass-insulated space - 20°- 140° - striving to repair someone's HVAC system.) What I'm suggesting, here, is that "playing music" is -
nearly always - quite "comfortable", and which is why so many enjoy doing it, and for no remuneration whatsoever. Arguably, even these - in the bitter cold (particularly if someone has one of those strap-on things in which to pee) - are more "comfortable" than many types of essential-to-human-existence types of work:
https://i.ytimg.com/vi/hq8HzYcEBh8/maxresdefault.jpg As I've suggested more than once, at least part of the attraction (particularly regarding one style of tuba, which - more recently - has been purveyed in less-expensive versions) is
appearance. (ie.
https://cdn.mos.cms.futurecdn.net/qRMx9 ... bRXdUd.jpg or even
https://i.pinimg.com/originals/a4/14/49 ... 66e79b.jpg )
Exploring another aspect of "comfort", some tubas are billed as "difficult to hold" and (after a mid-19th-Century Polish book was translated to English, just before the 21st Century, and the word, "ergonomics", suddenly became widely used in the English language) a few may actually be difficult to hold...but - in some cases - comfortable-to-hold postures either don't occur to some tubas' owners or - were it not that slide-pulling were necessary to achieve compliant intonation, if a particular tuba could just - simply - be held and played, that tuba would - otherwise - be "comfortable" to hold.
Playing tubas - for over five decades - I've encountered all sorts of models/trends/etc. (
@bort2.0 , I've even owned an Alexander C.)
I've hopscotched from "easy to play" to "amazing sound" and back...even AWAY FROM "easy to play"
and AWAY FROM "amazing sound" towards "everyone is buying these, so I guess I should, too".
The thing is this:
"amazing sound" is mostly a
myth.
Most ANY not-leaking/not-totally-a-piece-of-crap tuba's air column is capable of being nicely-vibrated, and an "amazing sound" can be produced.
The vast majority of rated-as-amazing-sound tubas (in my estimation) feature some sort of "amazing
feel" (yes: tactile, and even aural sensations can be classified - in some ways - as "feel") that appeals to its owner, or to its owner and to others. Further, I would offer that those listening to "amazing sound" tubas (who are not playing them) often listen with their eyes.
When a tuba features these:
> really easy-to-achieve compliant intonation
> really easy response (which includes all sorts of things/aspects involved in ease of execution and production)...
...that's a tuba that can be played WITHOUT having to play on it several hours each day SIMPLY to master/reinforce necessary quirky player strategies as work-arounds.
Those tubas - when found - are potentially joyful
and comfortable, but players also must be capable of recognizing those tubas and those characteristics.
(that I get from my autopilot/so-easy-to-play-that-I'm-not-aware-of-the-instrument-when-playing-it M-W 5450)...
(that I get from using the cimbasso that I built, and when the music director actually wants all I can produce from it)...
