Streams have a beginning and an end...
Is it necessary for all functions to work flawlessly, regardless of the parameters passed to them?
What should these exception handlers do?

For a test database, there should be infinite streams. Combining them into a single stream leads to script delays and the inability to perform its functions, plus a high probability of the script crashing. Splitting it into many streams leads to delays in the game itself.
For now, there is a way to use a mixed system: some parts sequentially, some in parallel, but as the system approaches infinity, the delay will increase. The most optimal solution would be to skip those functions that cause failures. Strangely enough, even a failing function can be beneficial.
In a single-player game, this is not so critical, but in a multiplayer game (not hotseat), it's a complete disaster!

There is a possibility of creating a stack-based replacement system, where one function is incompletely processed and replaced by another, in order to save resources. But such a system is poor for testing.

Added 5 minutes later
I will have to choose a simple, optimal system in which errors (stack-based) have already been eliminated, but also create a second environment for testing (parallelized).
I will test it and see.

Added 8 minutes later
The maximum number of active heroes on one map is 127. This is actually the limit of "infinity". But 127 simultaneous infinite streams is a lot!