The answer to this is: new wallet format is highest priority, especially now that we have all the multi-sig hooks in place. And we fixed the RAM issues... and we have resources to handle other things!
To address your points directly: we will have support for both compressed and uncompressed. Along with the ability to migrate old wallets. Compressed will be default, but have the capability to handle uncompressed.
Standard usermode, will by default, derive all wallets from the same seed, thus requiring one backup per user, not per wallet. But in Adv and Expert, you will have the option to create different seeds which spawn wallets with different backups, encryption passwords and security profiles. This is exceptionally important when it comes to offline wallets and multi-sig, having this flexibility.
The new wallet format will also have a much-more-flexible encryption scheme. It will allow for arbitrary data to be stored from set of different encryption and key-stretching options. It would technically allow the user to do very complex things, though none of those complexities will be default. But it allows us to build cool things into it -- like the ability to encrypt comments&labels with your publickey&chaincode, thus all your watching-only wallets can decrypt the data, and thus that data can be backed up and synchronized between devices (as long as you don't store the WO wallet with it!) Or multiple people in an organization can easily synchonize meta-data just by having the WO wallet.
There's a lot of cool things we can do with it. This only scratches the surface Stay tuned!
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P.S. - When I said this was high-priority, it was originally because we were really anxious to get some multi-sig features implemented, and we thought that we would have to wait for the new wallet format to do it. With the availability of lockboxes right now we are actually going to prioritize that first, and then work on the new wallet which will provide much more flexible multi-sig. Because, we want to take our time with the new wallets, and if there's already a usable multi-sig solution out there, then we won't be as rushed.
Oh my gosh! That sounds fabulous! :-)
"Stay tuned"? I feel like shortly before christmas here!
Oh boy oh boy! I really am happy with all that! :-)
Ente