Enquiry: is it better to have several BLE characteristics, or 1 with type in the message

This is more an enquiry than a problem.
From a performance and size of app perspective, for esp32 on arduino IDE and android phone, is it better to have multiple Bluetooth BLE characteristics, or a single characteristics and have the type of message embedded in the message?

For example: I need to send Voltages, Currents, faults, phase Errors, frequency and logs.
I can have the first part of the message be, e.g., [V] for volt, [A] for amp, etc...
or have 6 characteristics one for each.
the content of the message is short except for the logs, which in any case needs many 20 or 32 bytes chunks.

Also, I found in my search reference to BLE message limited to 20 bytes in some places and 32 in others. If I can have 32 bytes what do I have to set, and where (android, or esp32)