Ctrl+Alt+F5 - is it worth to change/add another shortcut?

I never used this one

now tried - doesn't work. Okay, checked support https://support.office.com/en-us/article/Excel-keyboard-shortcuts-and-function-keys-for-Windows-1798d9d5-842a-42b8-9c99-9b7213f0040f?ui=en-US&rs=en-US&ad=US - no sign of Refresh All shortcut.

Asked Google - appears what that's quite old issue. For example http://stackoverflow.com/questions/29149366/default-excel-keyboard-shortcut-ctrl-alt-f5-no-longer-works. Ctrl+Alt+F5 is reserved by Intel Graphics, even if it doesn't use it:

Internet has a lot of discussions how to disable Intel Graphics shortcut and return back default Excel behavior. Yes, that's a not a big deal, but you have to know about this.

These days quite many people have Intel Graphics on their PC:s and i guess 99% of them never use Intel Graphics shortcuts. On the other hand with wider usage of G&T with Excel you have to instruct end users how to refresh data in case of changes (if you try to avoid ActiveWorkbook.RefreshAll() macro and in addition to Refresh connection on opening the file).

Yes, Alt+A+R+A exists, but old style Ctrl+something by default will be more suitable.