I hesitate to write this, because you are probably already aware of it, but the “tacet al fine” feature - in its current form - doesn’t seem useful to me.
First, writing “tacel al fine” for a single empty bar in the end feels a little silly. But even if it was 100 bars, as a player I would prefer to see an explicit 100-bar rest. Knowing roughly how long it takes to until the end of the movement can be useful information.
The raison d’être for this feature, I would assume, is that usually you cannot actually write a 100-bar rest because it is constantly interrupted by key changes, time signature changes, rehearsal marks, tempo changes, fermatas, etc. Tacet al fine could combine empty bars even when normal multi-bar rests cannot, but it doesn’t do that (yet?).
In the future, if “tacet al fine” will be able to combine these things, I would still want some kind of threshold of complexity before it kicks in. If the end of the flow has to be split in 4 “sections” when using normal multi-bar rests, I would just use normal multi-bar rests. 40 sections? Tacet al fine, please.