Hi,
The project I am currently working on sort of includes a lot of what you are wanting in terms of using a mega and then using something like a smartphone for the interface.
Except what I am doing is for a renewable remote power system, but that is just the application.
So, the core control part would need to be re-written, but all the structure I think may be able to stay in place.
What I have is the Arduino doing all the control and logging to SD card while also being a webserver using Webduino.
I am using jQuery and jQuery-mobile to give a useable interface on smartphones. The web document is a 'MPD' mult-page-document, which I think makes it effective and efficient.
I will also then build up another web page for larger screens which will detail more on the one page, but this has yet to be designed.
The Arduino sends out json data messages to the client which is your up to date real time data that you want to display.
This can be all done via WiFi, 3g what have you.
If you are at all interested, then maybe check out the WebDuino library as well as the jQuery-mobile site and see if that is something you like.
Wow, I wonder how many people know what a Ham shack is, I used to be a radio amateur with aerials and wire everywhere, ah those were the days.....
You're not talking about a Ham shack as in the meat pork I hope? 
Paul