My bone is a modest Yamaha YSL354, a present/heritage from a close friend who died

I decided to learn to play trombone because I love the instrument and as a homenage to my friend's memory.
Since I have a background on tuba (elementary grade on tuba), I already have some skills as breathing or reading.
Now I'm playing on an amateur big band and I've been asigned 2 and 4 parts, so I'm considering to have another trombone with width bore and F attachment, or, even a bass trombone (I miss tuba's low end

I'm learning a lot by reading this forum. Thanks.