If they can fix the ergonomics of the R6, bring it up to current in looks (which won't be a problem I estimate given how great the R1 looks), and can bring it a few upgrades it desperately needs to be competitive then I'd consider one.
I wish more companies would do with 600s like they do with their liter bikes, and like Triumph does with the Daytona. Offer one bike with a lot less options, a lot less R&D, and offer it at a considerably less price as a result. Then give people the option to pay more for the bike with all the bells and whistles. The R1 is actually a perfect example, where you can get one with an acceptable KYB suspension, all the power, and a quick shifter (it's a cheap option you can add on from factory) for like $15,000. If you want the full on racebike R1M, it gets expensive. But instead of making one bike, they make both to appeal to both crowds.
I feel something like that would work great with more 600s. Make one that is cheaper and you can make higher profits on for most of the guys that just want a fast bike. Then make one, like the 675R, that is a great bike and a great option for those that choose it.