After a few drafts I am starting to settle on something like the following...
The parts are all pretty easy for me to come by. I have a few spare exarchs that I can de-wing, allowing me to glue the wing on the back of some bikes to represent the shining spear exarch's or autarch, and there are a few banner guardians my bits box as well. These will probably be restricted to one or two only, going on the command stands.
The bread clips are free, but I can't rummage them up very quickly, so conversion of the 32 jetbikes that I want to convert will be slow! (I'm making two formations of eight bases, with two bikes on each base similar to the regular jet bikes I already have like below).
The lances on the shining spears are the old epic banner poles with the base chopped off, and the end filed to a point to look more lance-like. I think that I'll paint them in a nice blue-glowy colour to help them look the part.
Getting consistency with the bread clip parts will be fairly tricky, as I'll have to be pretty neat in how I trim them. Which isn't really one of my strengths!
Another issue that I might run into is the fact that the models will be a bit wider than the regular jetbikes, and I might have to move some of them apart on the base to make room for the extra wing thingies. As the models are based and flocked already, on steel washers, that is a little more tricky than it sounds. I think I will trim some of the jet bikes off the bases, and put them on wire stands to make them a bit higher than the ones next to them, allowing the wings to fit neatly.
So watch this space, the Shining Spears are coming!