MacOS – Xcode word completion shortcut

The easiest way is to install bash-completion from homebrew and follow the provided instructions.

Example output:

==> Downloading https://homebrew.bintray.com/bottles/bash-completion-1.3.mavericks.bottle.tar.gz
######################################################################## 100.0%
==> Pouring bash-completion-1.3.mavericks.bottle.tar.gz
==> Caveats
Add the following lines to your ~/.bash_profile:
    if [ -f "$(brew --prefix)/etc/bash_completion" ]; then
        source "$(brew --prefix)/etc/bash_completion"
    fi

The Homebrew bash completion script has been installed to:
    /usr/local/etc/bash_completion.d

Bash completion has been installed to:
    /usr/local/etc/bash_completion.d
==> Summary
?  /usr/local/Cellar/bash-completion/1.3: 188 files, 1.1M

Once you are done, you can create your own scripts under /usr/local/etc/bash_completion.d/.

It is impossible to deliver an "answer" to this question. You are asking for something that is purely opinion-based. I have friends who use super small fonts and it's very comfortable for them. I also have friends who use larger fonts, and that works best for them. I personally use a variety of font sizes depending on what Mac I am on and what App I'm using. Your best best is to work with whatever font size suits you, despite what anybody else tells you.

There is no "one-size-fits-all" answer to your question.