I too just got some plans for the Turbinator-E. I started cutting a few parts and am going to try a foam core wing. About your first question,
you should be able to fly that with a 4s 2000 bat. I am using a 3S, 2350mAh 25C in a HET Sniper and it gets up and goes. I bungee launch this thing and have no problems. The Sniper uses a Wemo 480 w/Walkera 3900Kv motor and an Exceed 60A ESC it draws about 36Amps. Go to rcgroups.com as they have guys who are really into E-jets. I think that some type of tail cone however short may help. Here's what I mean.
From what I've read these ducted fans need good ducting to work better than having them out in the breeze. That tail cone is just a plastic Dixie cup cut to fit and taped on. A guy had a radar gun that the field and that plane did 78 mph avg. and again with a 3s battery. I need some 4 cells to go faster. More volts faster, more capacity longer flights. Another thing, someone told me higher C rating is what you need or jets, 25C -30C.