You only need to go online the very, very first time you use AxCrypt 2 on a PC. Thereafter there’s no such requirement.
The Premium price is not at all just for 256-bit encryption, it’s for much more! Including support, key sharing (work with encrypted documents with others), a password manager, secured folders and soon also mobile apps will be included in Premium. See http://www.axcrypt.net/pricing/ for the feature comparison.
Indeed there are free programs offering multiple encryption algorithms, but that’s part of the thing with AxCrypt. We make those choices for you, and in just about every case we do it better or as good as the user thus not annoying the user with a choice of algorithms.
Actually, if you like, you can plugin different algorithms to AxCrypt 2 if you’re C# savvy.