Bitcoind gui client, wallet client with peer preference, node manager
yup, see what you mean. Hopefully my answer is not disappointing. It is to my knowledge not existant. I'd reason this way:
I don't think it's the application, which should secure the network layer. Vice versa is the way to go on (layered approach). Create a secure network layer, and run the app on top of it. Otherwise all apps would build their own security layer, and I doubt there are enough security specialists...

The layers of the underlying OS allows to achieve security. 


  A very secure 'remote wallet' GUI:


define secure :-) Well, why not tunnel X over a VPN or through ssh?  


  A bitcoind full node GUI manager:


is the same. 


  A wallet manager application:


again, security built into the app is against principle of layers. You can tell your full node, from which IP to connect.