eltclsh vs Xonsh (The Xonsh Shell)

Tcl is a saner scripting language built on the same principle as the Unix shell (everything is a string) with more than a hint of Lisp. eltclsh makes it possible to use Tcl interactively with tab completion for both language constructs and file paths. The result is that you can develop a snippet of Tcl code interactively and then paste it in your script.

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 is currently not supported by TclVFS.)

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.

Most parts of xonsh are extensible. You can change tab-completer, prompt, history backend, aliases, functions and pack it to special package (called "xontrib") and put it on Github. The logic are clear and documented well.

The xonsh shell has AppImage that makes it Linux-portable.

Xonsh has one feature that can be considered particularly unique. It stores not just the commands you type, but their output, and doing a search on your history (configurably) can search the output as well.

Xonsh has native cross-platform support.