Unless you're going straight onto an airbus or a boeing, I am not sure how advantageous glass cockpit will be to you....anything smaller or less modern you will have a tough time on.
Duchess is a very easy aircraft to fly - less heavy than a Seneca and trailing link gear makes it land nicely even if you cant! Seneca is heavier - especially the underpowered Seneca 1 and a more of a pig single engine.
I can see the sense of a "less painful" ride in the DA42, and if it means that you're more likely to pass first time than thats a ££ saving. However, I also find it hard to believe that you will not be rigorously worked out (if not more so) in a modern a/c with all the hi tech avionics than you would in an old steamer.