I had shiny hubs on and it was having some issues when driving inverted. Not sure why. I'll try it again though.
I think you pulled the popup off better. Try using several 20cms on the wedges of the VS instead of one long extender. The wedges will be longer for the same weight.
I don't see why you aren't using the other APs on the disc, then you only need 4 extenders which will save you 8kgs into make the wedges longer.
For the VS, I'd recommend spinning the motor counterclockwise a little, it protects the motor better AND allows the use of more attachment points.For the pop-up, you need something to keep other bots from flying over, a few spikes or an extension of the upper wedge will keep bots in a prime position to gut rip. You might also want to think about switching to rubbers to improve the wedges further.
How do I get smartzones in stock?