Actually, if you get basic Sharing to be working and share the "Shared Forms" form, you can make the changes on one controller and it will be pushed out via SDS to all controllers.
I actually recommend trying to share as much data as possible, it will eliminate future issues with Local Directory Numbers, if they are in use and you want to start sharing some of them, you have to delete every instance in every controller prior to doing that. The more you share (and is in sync) the less problems you have later. Also remember with resiliency, all aspects of the device need to be resilient... for example, if you have a hunt group that is resilient, it is best practice to have all members be resilient to the same controllers, and all keys be uniform. This also leads into sharing feature access codes, system speed calls, class of service, class of restriction, etc... everything on a station level should be shared if any resiliency is going to be implemented.