We have to support the company first which has a more integrated solution that actually has to make money at the end of the day. We are also a pretty damn small team with a huge backlog to deliver, so it sucks that we had to abandon the UI outside of DCOS. We hope that the components of the DCOS UI for marathon can become the native UI for marathon, but again, it's a balance of priorities.
Marathon by itself has a lot more coming in the future, some will be restricted to DCOS, but not everything, it's a balancing act. Given our history of changing course publicaly (I wasn't involved in these decisions), I'm waiting to share our plans for 1.5 until I'm confident we're committing to them.
Just a quick two cents.
I wish you had forked it. If you're resource constrained and need to meet goals for LargeCorp, then fork the entire front-end/back-end. The approach of just ditching the UI half of the app while you iterate the same backend but with the DC/OS UI is really what's causing the grief here.