I could be wrong but I think the Codex reads that you can take Snikrot instead of a Nob not with. I might take those points and slim up the nobs just a little gear wise and see about getting another Defkopta or two. Using that Deffkopta could take care of one transport, and then again it could wiff and then die on the next turn. I like to run 3 defkoptas as single units and wreck house I know there is going to be more than tank in most list and I want to open them up as quick as I can. Then again they could all wiff and then die on the next turn

I think you have the right idea for your biker nob list. I just might play around with your support some and see what works and what doesn't. I mean you will be in someones face by turn two anyways, snikrot might not come on untill later if your dice are against you, by that time a good target might be gone or a mile away. I might try lootas and make it rain from 48" out. I'm not trying to knock your Kommandos idea. It should work, just be flexable try it a few times and then try something else.
Good Luck!