Nobody is forcing you to do anything. MQTT is very flexible, HA and Tasmota is very flexible. They adapt to any correct configuration.
But when you reach something like this :
You think about optimizing things 
Yes! And therefor I changed it :-)…I ordered 10 extra “tasmota’s”(ESP-01S’s) to use, below 2 USD to get information in HA and to control lights…
But I want to “understand” why this is. So are your devices sending stuff to the homeassistant topic? Or is it just a matter of “not sending” to much information to that optic in order to have homeassistant get overloaded by messages in there?
I just use the homeassistant topic for auto-discovery messages. So HA only uses this listener for creating devices.
Ok, think I am getting it… thus this looks ok:
and how can I change a name that HA has decided? I do this by shutting down the mqtt broker, delete the topic, restart HA, start container and then after name was set correct it takes the new name in hass… but there must be a more easy way?
If using tasmota, a new Setoption19 1 deletes the device in HA, and creates a new one with the new friendly name/ topic set in tasmota.
So, I did that on the “wrongly name” module, but nothing changed.
but if is did this:
Setoption19 0
and then
Setoption19 1
yes, that works… so much to learn
EDIT: this topic I will look a lot to from now