Yes, you can use an alias to overwrite a command. In fact, this is already the case for ls as default this is aliased as ls --color=auto

Create a file called '~/.bash_aliases' and enter the following line

alias ls='ls | more'

Now when you type ls in your terminal, it will instead execute ls | more.

In this case it does has an issue with parameters. ls /some/directory will not work anymore because the parameters are applied to more instead of ls (ls | more /some/directory will be executed)