Putting a component set up high, and another down low, will hurt imaging/staging. If that's not important to you, it will certainly help the 'in your face' type of sound. Id still consider coaxials over a comp set, a single point source that close to your face/ears might be desireable over component speaers mounted side by side.
Also, putting a comp set in the A-pillars would cerainly hurt low-end output (designed for IB), but you'll be running dedicated midbass so that's not a big issue.
For midbass, why not consider a couple pair of EU-700's (staying with the eD theme)? They are certainly midbass drivers, and 2 pair would deliver more midbass than you'd need realistically. Just a lil more cutting needed to the door. //content.invisioncic.com/y282845/emoticons/wink.gif.608e3ea05f1a9f98611af0861652f8fb.gif
Good luck with your new setup, keep us posted. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif