Can I sign created transaction with this new release 0.95.1 using an offline version 0.93.3 ?
Yes
Do you plan to make an updated standalone / offline bundle, dedicated to cold storage and offline signature, compatible with a more recent OS than ubuntu 12.04 ? (like a 16.04 LTS or tails 2.9) ?
I have not built any offline bundle myself. These are just carryovers from the ATI era, since I have not changed the signing code yet.
There is new signer code to cover the new address types for 0.96. This code is only active when spending from the new address types, this means you can use the old offline signers to sign for the legacy addresses funded with 0.96 and later.
If you use the new address formats, you'll need a 0.96+ signer. For that purpose I'll put out a new set of offline bundles.
Offline bundles aren't just builds however. They come with the packages needed to install Armory offline on the fresh install of the target OS. Assembling and testing the packages is a demanding task on its own, which is why you won't see offline bundles for every release, and only a few OS supported.
I use a different process than Alan for builds however. For each package, he would build the binaries directly on the target OS. I build all *nix binaries on Debian Wheezy. These binaries are compatible with everything Debian x64 based.
This leaves the question of OSes and arch. Obviously there will be at least one Ubuntu LTS. Other OSes are still up in the air atm. As for Tails, afaik they run on Debian Jessie, so a Jessie offline bundle should work, although I believe they use x86 and not x64, which is annoying in its own right.