Smartthings to home assistant gotchas?

Haven’t taken the plunge to switching from Smartthings but trying to do my research first. What gotchas can anyone tell me there are with using home assistant?

Right now I can:

  • have alexa announce when an open and close sensor is opened or closed (I.e. announces when the garage door is open and closed)
  • I can have alexa run routines from Smartthings for me
  • I have double tap enabled on some of my GE z wave light switches
  • presence detection (have read a lot on this and there are some options I know of - really curious on using BLE sensors because it seems you can use multiple?)
  • I can launch routines using the Smartthings app or a button press. - how easy can I edit routines or automations using home assistant?
  • I like the aspect of HA to keep everything local but I see it depends on the devices I have whether they will be truly local
  • can you run adjacently devices that work natively with HomeKit and exclude them from the HomeKit component of HA to just use the native support?