Thanks (everyone) for the info! I've added a $75 lighthouse to my order. Hopefully, I won't need a controller to setup Steam VR.
While I do care about SDE, I can't really justify spending the extra cash to get the 8K. There's some discussion about the 5K's display technology and even the possibility of selecting between OLED and CLPL. If so, I'm torn: OLED will have better blacks and more SDE and CLPL will likely have less total contrast and reduced SDE (not due to pixel size, due to pixel coverage). DPI is only part of the issue; pixel coverage seems to be more important (smaller pixel coverage has more black surround). From the Kickstarter page: "A 5K resolution is good enough to eliminate screen door, and ideal if you are not as deeply concerned about pixels."
If I have a choice, I guess I should get the CLPL.