I'm having this problem right now. Simulation/Entity type object model is working quite well for one app, but add another app and the cracks in the abstraction

I'm having this problem right now. Simulation/Entity type object model is working quite well for one app, but add another app and the cracks in the abstraction become obvious. Using dynamic properties for the app-specific properties seems to help contain the problem. Also, putting app-specific code in extension methods. I see this problem as a limitation of our current tools. Splitting the object model into separate perspectives is too hard right now.