I didn't know about the GFC700, but is it truly VNAV? can you input your SID's and STAR's for instance and expect it to follow them? Or do you have to set an ROD manually?
It certainly isn't beyond the realms of technical ability to come up with an autothrottle on a piston a/c, certainly not something that has a single power lever controlled unit with FADEC.
Why isn't there a fully integrated system like we have in something like a 737. They aren't exactly the latest technology but seem to be far in advance of something like a G1000. Yes, it maybe a more compact package, but why not have the full functionality?
At the moment, they are better than your average "steam" instrumentation, but with reliability issues (Yes I have heard of a few problems with screens shutting off etc.) and the fact that for basic flight they can be overly complex. I personally can't see the point at the moment apart from sheer techno-geekery.
IO, I think you're right about training people to use a full suite of avionics, it's amazing how many have never seen a DME before!
I think the article was in a recent edition of GASIL or Safety sense, but I whole heartedly agree with the sentiments.
When I first started on machines with EFIS, that was what took the most time to learn and understand, not the fact it had a couple of jet engines and went 3X as quick as anything I'd ever flown before, but how to interpret the information given. I even found myself relying on the standby instruments as they were far more familiar!
However, once over this initial reluctance, EFIS does make life an awful lot simpler, but it does take training to use properly and especially all the features available. Reading a manual is OK, but a structured course would be far more sensible.