I believe that Pimax is on the right track. They seem to be focusing on getting the headset into 'production ready' condition first and foremost. Getting the headset's issues resolved and then putting it into mass production is obviously their first (and most important) step that could either make or break Pimax. Fulfilling the 'headset only' orders for the Kickstarter backers will generate a lot of good press with the media and drive orders for future sales. Given the Vive Pro's incremental resolution bump and no FOV increase at all, Pimax is still in a great position to vault themselves to the top of the VR pack. Everybody wants to purchase headsets with higher resolutions and a wider FOV, but nobody seems willing to offer it. Yet.
I'd imagine that their lighthouses, being a reference Valve design, are basically ready to go. Hopefully, Pimax can also work with Valve to get the knuckles controllers up and running as well for the people who backed the full packages.
Having said all that, it's still important for Pimax to continue working on the components for the stretch goals afterwards. Remember, their goal here was to create an entire modular platform, not just an HMD/controller combo like every other player in the VR market right now.
Once the 5K/8K/8K X headset designs are perfected, Pimax won't need need to worry about redesigning/updating them for some time to come. I highly doubt that any other manufacturer will be surpassing (or even matching) their specs for some time to come. So the Engineers at Pimax should be free to work on the accessories at that time.