How to partially overriding locale?

Hello, I wish to customize the home page, a part of it is changing text and having it display in the appropriate language.

I currently create a whole new tmpl file for the pages requiring aesthetically changes and each element have it’s own file, but it looks like the locale is one full file per language.

Is it possible to override only a specific part of the locale file to not have the burden of maintenance of verifying it after each release?