I love the idea of using the wide array of optical sensors and weapons that were available for the GR7/GR9 in DCS
I think the best thing is that any mission for the A-10 could conceivably be used for the Harrier (maybe with minor modifications like probe and drogue tankers) so we've already got an incredible amount of content for it.
The lack of radar doesn't really bother me I don't think, we already have much more capable fighter aircraft than the harriers ever were in DCS (Mirage 2000 obvioously is an example)