As far as I know JSON rpc is usually HTTP type requests by default so no there shouldn't be any CPU cycles saved here just more typing and confusing of "object handlers" if I could enable TCP mode for sure, I'd implement the global "object handling" feature infact I'm writing that down in the "TO DO" list "Research how to enable TCP mode in the BDKs' current JSON library".
https://github.com/Xenland/Bitcoin-Development-Kit/wiki/%28%29-To-Do-Features-%28Notes-to-contributing-developers%29
I'm not talking about CPU cycles, I'm concerned about network traffic. Not everyone is going to have their RPC server hosted on the same machine as their site. I'm willing to best most actually go the 3rd-party route, and outsource their RPC server.
As for "creating an object", the jsonRPC library already returns the connection as a class object. All you need to do is have it set as public at the top of the script (after including jsonRPCClient.php and config.php, of course).