Integration with VS to display introduced elements in partial classes

I can use compile-time generated elements from my run-time code by marking a class as partial, but I still get all sorts of disconcerting red squigglies when I do so and don't get to benefit from any Intellisense regarding the types of anything I introduce. I don't know to what degree you have control over this, but it'd be amazing to be able to attach an aspect to a class, mark the class as partial and then utilize the introduced members as though they were part of the code I'm typing right there. Take this first screenshot example where the _elements field is introduced by the InsertProperty aspect typed according to the type passed into the TargetType attribute. It works and when running the program I get the line added there, but t's not clear from eyeballing the class that this would work without explicitly trying it. Getting the visual confirmation that the IDE thinks it should work right without it citing all these errors (screenshot #2) would be a huge help.