It helps to think about the underlying protocol/connection that that the hub is capable of making to other devices.
In general, there’s zigbee, z-wave and WiFi/Ethernet (which are both ways to connect to an internet protocol network).
You’ve got quite a mix of devices, as you said, so compatibility with Hubitat varies.
Hue - Uses zigbee but the built-in integration with Hubitat is actually designed to connect to the Hue bridge over your Local Area Network (LAN)
Eve - not personally familiar with the brand, which protocol do the devices use?
IKEA - mostly zigbee devices I think, some are on the hub’s official compatibility list and can pair directly with the hub
Bond - you need the bridge to control RF or IR devices, but there is an integration written by a community developer to allow communication with Hubitat
Blink - proprietary system that will never work without its own sync module. In the past, there have been community-developed integrations with Hubitat but I don’t know the current status of them
Nest - depends on which Nest device
Switchbot - Also can be integrated with the Switchbot hub thanks to a community developer’s work
Leviton - They make a lot of devices, so it depends which protocol yours use. Could be WiFi, or z-wave
Your treatlife bulbs and switches are probably WiFi? If that’s the case, they would need a specific integration like any of the others above that connect to your LAN with WiFi (or Ethernet). I don’t know offhand if there is one for Hubitat.
Depending on how exactly your DIY blind controllers work, it might be possible to integrate with Hubitat directly without needing to use Node Red.
