Yes, definitely a template layout.
Also, create your button bar such that, wherever possible, you can change all the copies in one place.
An obvious way is to ensure that your button bar uses a named style.
Also, consider running your buttons through a single "switching" script that takes a parameter and, if necessary, performs the subscript(s) appropriate for that button. That way, you can change the behavior of, say, the third button on every layout by changing one script.
Finally, I'd advocate heavy use of custom functions for tooltips, hide when, any conditional formatting rules, script parameters and even the names of the buttons. The cf's need not be complicated, and might even just be text strings, but that way, you can change any of these things, on every copy of the button bar, by changing a single custom function.
Then, focus on the aspects of your "template" button bar that cannot be changed in one place. For example, the position in the header, the sizes of any popovers, svg image backgrounds on buttons, colors selected for conditional formatting, etc. Make sure you're happy with those, since changing them later will require, at least, copying and pasting your template button bar on every layout.
Do you want to use the file in webdirect?