First of all, Calculate & Compare got me by surprise. A very cool feature, thank you very much for it! Of course having this features allows for more options.
What I would like to do is compare a certain route between airframes. For example, I was looking at a flight between UK and USA and wanted to compare the BBJ1 with an A330. But only allows for comparison over the same airframe. It would be nice to have the option to compare different airframes too.