Jasper Ave is fairly long and much of it is fairly developed, but there does seem to be a few big dead spots still and they do seem quite resistant to being filled for whatever reasons.
It took years to develop the area around 109 St and Jasper, which is now fairly bustling and some progress seems to be happening just east of that, so I am hopeful that will improve soon.
I do think the Edmonton Motors site has a lot of potential, so I hope it will happen without great delay. I think it is the key, once it happens the other sites in the area will also be developed.