Just some comments, as I also thought about them before, but did't have the time to implement:
OLED
Energy Saving or Dimming mode for overnight
Prevents too early Burn in Effects, that OLEDs unfortunately have.
still was not very easy to determine the time, when to dimm / shutdown the display as it can be that we run standalone withouit any external clock --> RQ: Needs NTP?
MQTT Client Name
Add better compatibility and settings for MQTT client
User specific client name
User specific Main topic
Options for Smart Home Systems (currently only HA is supported and tested by me)
Display Mode
Maybe only show the data if everythings works as expected
More verbose output only if something seems to fail
currently is is more made for developers and shows a lot of info
Request for enhancements:
By the way: mqtt output of spidr is also running with fhem smart home. device will be added automatically as device MQTT2_DEVICE_MQTTClient in fhem