I currently make about 8-900 mil an hour clearing C4 sites in WH space. I would say that the absolute minimum to run them efficiently would be 5 accounts--Two T1 Logi is enough to rep through any wave in a C4 provided you're not killing the triggers early and applying your DPS appropriately.

I ratted in NS a few months ago, albeit with a lot less skill points, and I firmly agree with Mokoi that any multiboxing fleet is overkill in NS. Even if you warp each individual ship to a different haven/sanctum and have them setup to passive tank them you're not gonna generate more than 200m an hour. Of course, the worst part is that you're going to clear ALL of the anomalies in an hour or two and then have no money to be made.

In WH space you clear your static WH's sites and then just crash the hole and scan down your new one. It is a time investment to roll it and then scan down the new one, check for life etc but it means that you can do the ISK dance indefinitely.

As for D-scan... Yeah. You do. At the same time, if you've scanned down your prospective farming static appropriately you're gonna' know if there are inhabitants that will put up a fight, and/or if there are people further down the WH chain that will fight with you.

The great thing, nay the best thing, about multiboxing in WH space is that you singly represent a huge fighting force. In NS even 10 or 15 ships is a gift to a blops gang. In WH space, my fleet of 20 ships is king.