Tracking email conversations with Omnifocus

I have tried to use Omnifocus to keep track of crucial emails, but I find it not ideal. Perhaps it is because I feel it is too easy for them to get lost inside the system. Or perhaps is because transferring an email from mailplane to Omnifocus is too cumbersome for me.

As a result I end up leaving unfinished email in my inbox. This like wise doesn't suit me.

Has anyone mastered the art of tracking emails (with Omnifocus)?