Ehh, uber eyecandy campaign is probably BWO, they've got this really freakishly beautiful background with the moon and the Earth and... wow...
But Inferno is, in the feel and atmosphere, IMO, FreeSpace --- Three. My only worry is that Inferno SCP may have a different atmosphere than R1.
(please do not smite me for this too)
Screenshots never capture the actual 'atmosphere' of a mission, there was a trailer a while back where there was a Kabechet, Hedetet and Apothess against a Shiamak and a Yama. The feel was really good, as in, it was like a 'problem' rather than a battle at the beginning. A screenshot would probably have given the impression of "Ehh, big battle with Shivans, whatever," But the trailer gave you the feel. I hope that mission is still in Inferno (probably isn't, pity).
Alliance will most likely capture the feel of FreeSpace 1, which is much different from the feel of FS2.
Anyway, I don't think Alliance or SCP will be crap because, well... it's Inferno. 8)