Is there a 'too early'? I'm bearing in mind the OP's point - that he was thinking in terms of a
personal sound (and not so much a 'good' sound.
I'm not a teacher, and - as my username suggests - I play baritone horn, not trombone; this is totally a personal point of view, and I'm throwing it into the ring as no more than that.
My initial contact with brass bands was when I was a small boy in the East End of London. Just up the road was a Salvation Army Citadel, and on Sunday mornings their band used to come and play round the street where I lived. We're talking over 60 years ago, mind, yet the sound of their band is still crystal clear in my memory. My next contact with brass was marching to military bands in the late 60s, when I was in the RAF - and I didn't think much of them at all! I wasn't struck on any of the woodwinds (or saxophones), thinking them completely out of place in a military band, and would gladly have made a bonfire out of those horrible, screechy piccolos!
I didn't start playing brass until I was 68, but, right from the off, I knew
exactly what sort of sound I wanted to make - and that was before I had even made my first buzz. I know this man, Bert Sullivan, is playing a euphonium in this piece ('Endearing Young Charms'), not a baritone horn - but just listen to his articulation! None of those notes are tongued at all, but you can hear every one of them distinctly:
Bert Sullivan playing with the Great Universal Stores Band, in 1960.
So I've been told, back then the bore sizes of all brass instruments were significantly smaller than those on current models - and can't you hear it? Watch the video through, and listen to the sound of the whole band - that's exactly what my local Salvation Army Band sounded like when I was still in short trousers, and I knew that was exactly what I wanted to sound like, even before I started.
In total contrast, this piece ('Carnival of Venice') was recorded by Bob Childs 25 years later. Some people like it - I find the whole sound fluffy, woolly and blurred, and to me the sound is totally wrong
for the piece he's playing. There are some pieces of music which really call for a smooth, flowing sound, and for that, you can't beat a euph - after all, that's what euphs are made for! But not this one:
And, to top it off, listen to 'Endearing Young Charms' played by David Childs, in 2012.
Listen to that first run of notes, starting about 20 seconds in; can you hear every note as distinctly as Bert Sullivan played them? NO chance! He's blurred them into a horrible, discordant screech. It sets my teeth on edge so much it makes me think of fingernails drawn across a blackboard.
I've seen posts on various forums from American brass players who've said that, in their opinion, "a baritone horn should sound almost like a euph." Really? WHY? If you want a euph sound, give it to your euphs to play! A baritone is
supposed to sound as different to a euph as a trumpet does to a cornet, because it has a different job to do in a band - that's why baritones were invented, and why they have far more parallel bores than do euphs (just like trumpets do as compared to cornets!)
So has my focus on that 'personal' sound confused me or held me back? I don't believe it has, and none of my teachers have ever suggested that I ought to forget about that and focus on the nuts and bolts. And nor have any of them suggested I should try to "out-euph the euphs".
I can say, hand on heart, that if my MD told me he wanted me to sound more like the Childs than like Bert Sullivan, my response would be "Goodbye."
It might be worth pointing out that, if I was asked to switch to a different instrument in the band, the only one I'd really be happy to have a go at would be a tenor trombone - because of that lovely, meaty, gutsy sound!
Baritone Jack