I have used Macaroni in the past to remove localizations; however, it doesn't
support OS's past 10.6. The one thing great about Macaroni is it would not
allow you to remove English. The developer stated in FAQs that the English
localization had to be there for the OS to function.
Seems that this application allows a user to "shoot themselves" by offering an
option to remove English. Would suggest the developer remove the English
option to make this fail safe.
Yes, it makes sense to exclude English if you let Monolingual clean your complete system partition. However, you could configure it to process only selected applications where you know that they run without the English localizations. I tried to make a compromise by disabling English regardless of the language you're currently using but you can still enable it (which will also issue a warning).
Thanks for your reply.