You asked about making a living just with arranger play.

Lots of folks I know (me, included) are generalists (some call us "music whores").

I do 25% of my jobs on arranger, about 25% on solo guitar and the rest as on sessions, as a sideman or with the groups
I have (trio, 4 piece, 16 piece).

Just suggesting you evaluate your abilities and make the most of things (keeps things interesting, too)!

Everyone does things differently; this is what I do, and it has worked for me for over 55 years.

Also, music is one product/service offered by my company, which also includes a variety of communications services, so while music isn't the sole source of business and income, it it a "mainstay part of the product/services offering (think sound scores for films, broadcast jingles, corporate events, etc.

Good luck!

Russ