I agree a 60 mile plug in sienna would be nice. Although my parents made us stuff into a 4 door 90s sedan until we were full grown so I think a prius could work. So don't spoil those kids too much
A sienna hybrid gets 36/36 and tows 3500 though. Thats pretty impressive. With the insurance on a 3rd vehicle being some what expensive i think a sienna to replace a tow vehicle and a econo box would be a good idea.