Congrats on your new LC.
I installed a THINKWARE U300pro front and rear dashcams…works great…only challenge is to download files, you need to disconnect from CarPlay to allow Wifi link to the unit…besides that, works like a charm. Not cheap but I guess you get what you pay for.
In terms of the roof rack, I have really wanted to install a full rack but it does require the removal of the OEM rails (not a big deal)…my challenge at the moment is clearance in the garage at my work…
If you dont want to remove the rails, then an option is Thule or Yakima cross bars that allow a large basket for gear, bike racks, canoe and ski etc and you can easily dismantle if needed…IMHO though, if you are thinking overlanding then a proper rack is the way to go…likely under 1500 USD installed depending on source.
Good luck!