Looks pretty good. Only suggestions I would have are:

If possible in your server configuration (or .htaccess if this is a shared server) set the ServerToken to Product Only. This will prevent the forbidden message and the server headers from displaying the version of Apache you are running.

I see you blocked the /templates/ directory as suggested by amxfan. However, it may still be possible to guess file names and use other (possibly yet undetected) vulnerabilities to execute files in that area. May I suggest, remove the /templates/ and other sensitive directories from your robots.txt file, and replace the 403 Forbidden response with a 404 Not Found? This can be done by removing the allow/deny rules you added to .htaccess, and replacing them with:

RedirectMatch 404 /templates/.*

This will cause your server to display your customized 404 error page instead of the current static 403 forbidden message. It should be friendlier if a user does get to that folder by mistake, and should also help with security by hiding the folder.

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