My latest project is just about finished. It's a squad of 5 bikers with a Power Fist and 2 Meltaguns. The Meltaguns were spare parts from my Centurions and are mounted on the front wheel, a bit like the FW Legion Outriders.
My original idea was to give my Master of the Forge some protection, but I'm now planning a biker Captain as well to make them troops. A mounted Command Squad with an Apothecary and Storm Shields is also very tempting due to its survivability, if expensive.
At the moment I can't quite decide on what chapter to do any more bikers. Whilst Storm Lords allies would look good with my Griffons, and are White Scars successors, a homebrew chapter would be useful. I could choose any doctrine I needed and so this would be more flexible. For now I may well just stick with my Griffons and just get a couple of decent bike squads, probably with more grav weapons to hunt MCs.