My brothers still collect the 3 3/4 Joes, my BAT collection is mostly 3 3/4, and even little Haywire 3, who is 4, has started a collection of 3 3/4 figures that has been augmented with The Corps, Spinmaster's DC figures, and even some Kid Connection vehicles, along with thrift store and garage sale finds.
The Classified figures are pretty to look at, but between the price and the difficulty of getting vehicles at that scale, they just aren't that great as toys. However, if Hasbro won't support that scale, there are still options out there.
EDIT: and, honestly, that Dragonfly is cool, but our holy grail was finding the Processed Plastics helicopter that stood in for our Dragonfly when we were kids. It would have been easier to get a real vintage Dragonfly, but nostalgia is a helluva drug...