I suspect the latest changes are a function of the garbage Tesla catches from Wall Street and the financial media if they fall a bit behind guided margins (they got tarred and feathered a couple of months ago for 1,400 cars being shifted from December delivery to January. No real impact on anything, but a perception game field day for Tesla's critics).
I think with the $75K 70D offering better value to the customer (and less margin to Tesla), they had to make up a bit of the margin they would otherwise lose by tweaking pricing of options. This lead to the bemoaned $5,000 Premium package. With the complaints about that $5K price (which, fwiw, I agree with), Tesla realized they had to switch to something more reasonable, and now have priced that package at $3K. To make up some for this decrease, they axe all but one token non-premium paint color, so the vast majority of cars pay for premium paint, among other small margin friendly changes. I think it's fair to say this is all somewhat a shell game, but it does seem the 70D is a better value than the 60, and, as widely discussed, we may see a similar move with the 85s soon (what's more some nice value got added in the fall with the new autopilot hardware).