First off, I've fallen in love with Studio One (3). It echoes the amazing versatility of MTV Music Generator 2 back on the Playstation 2. For me it trumps my old software, Cubase 7 in very aspect - except one. It's inability to play nicely with other DAW's. Previously, I used Reason 10 with Cubase effortlessly, mainly for it's Dr. Rex's and Combinators - something that is an almighty effort now - to the point that I've stopped opening Reason. To merely test the sound of a Reason instrument with the Midi keyboard a new track has to be set up in Studio One,then rerouting in Reason has to be performed followed by the creation of a bus to route the two mono channels from Reason panned left and right to that bus.
Please correct me if I'm wrong.
If I'm not then please, please take another leaf out of other DAWs, by letting the Midi controller be used by both slave and master DAW simply by selecting an instrument channel that you want sound to come out of.