When live view was fitted then the capability was pretty much there.
The 5D2 added a new sensor and processor to the 5D spec so it's difficult to see what cost the video feature added.
The 7D added a new a new sensor, AF system, pentaprism, wireless flash and twin image processors, and a dedicated AF processor to the 50D spec, as well as video, so it's hard to deduce what extra cost the video function indiviudually added.
The 500D added a new sensor and LCD screen to the 450D spec, so again it's hard to isolate what cost difference.
I don't use the PIC modes. Never have, never will. I don't use spot metering. Unlikely to. I don't use AWB. Not likely to. I don't use custom profiles. Unlikely to.
Canon don't make a camera specifically for me, but they make several that do what I want, so I put up with the redundancy.
I do use video, for my work. And as great as it is, the video is compromised by the still sensor roots, not the other way about. The AA filter is the wrong strength for the ultimate video resolution. The colour sampling pulldown isn't great for video (4.2.0 where 4.2.2 is the norm, and 4.4.4 preferable) the sensor read-off is wrong (very slow version of frame transfer, rather than the preferable and switchable frame / interline transfer FIT type) causing the infamous jello shutter.
So if anything, stills considerations compromise the video capability, but then, it is a stills camera first and foremost.
That said, used with realistic expectations and sensible techniques I prefer shooting on my EOS camera for many types of job than on my 2/3" ENG camera.
Back in the day when I used an EOS 3 film camera, I loved ECF. Some folk hated it. I could never work out why they just didn't use it. I would swap PIC modes AWB and spot metering for XLR inputs and a headphone out, but how popular would that be?
You will find it difficult to buy a camera without video these days, so regardless of the answers you come up with, thats how it is.