Generally speaking, there is a certain risk of breaking something else when changing seemingly non-essential / non-important little things. Let me explain.
The current DOS-based boot and menu system used in UBCD is not being maintained anymore by the original developers. So any changes made there, must be tested and reviewed in different situations, with different type of programs being booted and in different hardware, as it would be a customization in UBCD. Remember that the original system was made for several different DOSes too.
Let me give you an example (among many). You could try changing the "VOLUME_ID" value in several scripts. It is, seemingly, something that shouldn't be of any importance. But the same value is used in mkisofs for different fs (and each fs has different restrictions regarding this value), and it is also used in (Linux and/or Windows) scripts. So the value used in "VOLUME_ID" shall respond to different restrictions, but a common user might want to change this value without knowing about such restrictions. BTW, there are more than one "VOLUME_ID" variables in UBCD, and the most restricted case responds to 11 upper case characters.
There is one additional layer of scripts (not necessarily included in UBCD), that is used when building a new official release.
Now, going back to the particular case you present here, the only case when this needs to be altered would be, as you explained, when a user wants to have more than one fdubcd AND also wants each fdubcd to be identified differently in the specific fdubcd menu.
In most cases, the user would edit the same fdubcd so to customize it and re-build it (mkfdubcd scripts), leaving only one customized menu. For the fdubcd system included in each release, there is no need for more available characters for the VERSION setting, so the official releases don't really need this particular change.
Additionally, in some cases (although, a little different situation from your current one) the user would simply add a complete separated floppy image to run a custom DOS program instead of adding it to fdubcd.
Once in a while I am very tempted to customize the scripts in fdubcd with improvements (for example to have a different control over the booting process, depending on the specific DOS program to be started), but usually there is not enough feedback or testing, so I'm then discouraged.
Please don't misunderstand this post. When an update is convenient and practical (for example with new versions of DOS programs, like memory managers or drivers), changes shall be done. And sharing our own customizations is always welcomed, thanked, and useful for the improvement of UBCD. So please keep sharing them, and Victor might decide to use them in future UBCD releases.