This all sounds perfect for me!
I just recently bought Elite: Dangerous in its Deluxe flavour plus a year's worth of PS Plus, so I was in for a good heft of money, but I was convinced from the trailers and reviews that it would be worth it. However, to my great shame, I wasn't even able to complete the tutorial missions, and eventually just gave up, telling myself I'd take another try but (as of yet) not quite ever doing it. These hit the exact issues that were proving to be such a problem for me. Thank you! (And hats off to all the seasoned players who didn't have any trouble with this stuff in the first place.)
My one big question: You mention that some of the content will be available to any commanders who haven't earned their first Combat, Trade, or Exploration rank, but that the modules will come with all newly-purchased ships. If we tried our hands at the tutorials but didn't ever actually launch the main game, then we start after the April update, will we begin with the new modules installed?