Are you keeping the Trademark 60? From looking at the specs for it you can use a multi-effects unit in the loop (use the 4CM to hook it up) and you'd be okay. You'll be limited in what you should expect for patches unless you're willing to go all-in with the ARMD MIDI Converter too.
http://www.tech21nyc.com/products/amps/guitar/trademark60.html
What I mean is that if you really want to get to a spot where you're just hitting one button and getting amp channel changes and effects presets, you'll probably have to go with some sort of MIDI-enabled system. if that's the case then either the TC Electronic G System or the Boss GT100 will do what you want.
If you don't want to go that far, then a good multi-effects unit through your effects loop will get you pretty close. You'll still need to have the footswitch for changing the amp's channel, but you can run either the Boss GT100 or the TC Electronic Nova System that way.
I've got the G System and it's really really really good. I control my amp through MIDI and have all my effects minus wah (you can pry my CryBaby from my cold dead fingers) running from there. I've got three presets set up that include channel changes on the amp, and presets for each of the effects. One touch and I'm where I need to go. Plus I've got three of the buttons programmed with CC commands so that I can hit a preset for the clean channel where I've got chorus, delay and boost enabled, and then get to a good crunch by hitting one more button to change to the gain channel on the amp. Tap, Tap and I'm there. The cost for the G is a bit prohibitive (~1K US used) but it was worth it to me for the flexibility I'm getting out of it.
The TC Electronic Nova System has most of the same effects as the G System and can run in front of the amp or out of your effects loop and is much more affordable. But, you lose the ability to do patches and MIDI for amp channel changes with the Nova.
I think from what you said KS, that you're going to want something that isn't just effects though. The G System and the Boss GT100 will do that for you. If cost is a limiting factor, then go for the Boss GT100.