If you go to View/Options you can change it to 256. From time to time it will change back to 16 (eg if you download a different program to an 08/08M), but just change it back to 256.
I tend to use lots of gosubs as the code in the main routine ends up simpler to understand. Technically, you don't need a gosub for a routine that is only called once, as you could just paste that code into the main routine. But it is easier to understand with gosubs - especially if you document which variables are used and altered by that gosub.