What about the whole length of Adelaide Avenue/Yarra Glen & the Tuggeranong Parkway? They are both access roads to the Woden Valley/Weston Creek that have only flyovers (except the big roundabout).
Now Smitho, could some of the planning/money set aside for Belconnen of been used to pay off WW2?
The Parkway goes around the back of Woden and is a major arterial road that Belconnen doesn't have nor need, unless you count the GDE which is built to the same spec but clearly came much much later. As for Adelaide Ave, yes it does indeed have a couple of fly-overs, but as you point out once it gets to Woden proper it hits a big roundabout and turns into any other dual carriageway road. If we are going to have a tit for tat on flyoevers, Belconnen does have two, one next to the mall, where the bus road and Joynton Smith cross under Loxton Street and also where the bus road passed under Chandler street at the end of the old interchange.
As I said I don't beleive there is any major difference in road design. Both were done to a standard much higher than what is done now, with the future in mind. The only roads in Belconnen that I beleive were orginally done poorly are Kingsford Smith Drive over Mt Rogers, which should have been dual carriageway, rather than single carriageway dual lane all the way to Kuringa Drive, and William Hovell Drive which should have also been from day dot, or designed as a dual carriageway/built as single carriageway until demand required it.
If there are issues in Belconnen now it is simply because the road system hasn't kept up with developments. One such example is the Lathlain Drive extension to Belconnen Way. Very poorly done and see's a lot of traffic, maybe more than the designers first though. I see recently they have removed the option to turn right onto Belconnen way from the left hand lane. I presume due to cars in that lane blocking cars wanting to turn left, though from what I've seen since it was removed cars still get blocked anyway as there isn't enough room between the entrance to Bunnings and Belconnen way for all turning cars to queue so the back up towards the enterance to the front of the markets. Again the whole thing should have been dual carriage way with lights to the Markets, Bunnings and Belconnen way much better syncronised.
There are also a number of roads that were designed for future expansion, read duplication that maybe should be done but haven't. IMO Kuringa Drive from Kingsford Smith Drive being one, along with Aikman Drive and William Slim Drive. There are also some roads that have been buggerised by recent developments, Ginninderra Drive being the prime example with all the bloody intersections and lights it now has, none of which are syncronised.