When you start typing a command, you can press the tab key and it will complete the command you started typing. If there are multiple potential commands, you can choose which one to run by simply pressing tab again.
Xonsh uses a syntax which is a superset of Python 3.4 plus some additional shell primitives. Because of the similarity to Python, which is famously an easy to understand programming language, the syntax of Xonsh is pretty easy to grasp too, even more so for Python programmers.
The Bourne shell has always been criticized (most notably by Bill Joy, author of csh) as being unfriendly for interactive use. It has no tilde (~) expansion. Limited file test operators. Limited math operators.
TclVFS allows you access files inside ZIP archives or on remote HTTP and FTP servers like you would local files. If you put "package require vfs::urltype; vfs::urltype::Mount http" in your ~/.eltclshrc you can do things like "file copy http://example.com/file /tmp/file" (HTTPS...