Your chinchilla colored doe looks a lot like one of the offspring of my former Flemish buck and Former satin doe. My Flemish buck, despite having hefty parents, just never reached the ideal weight for a Flemish. He looked fantastically healthy, but I guess he got the short end of the genetic stick. .. .... and I say "Former" because I was not happy about the growout rates. Your rabbits actually sound on par with mine as far as growth goes. I was unhappy with the slow growth, the very underdeveloped shoulders and forelegs, and the heavy frames. Now, my Flemish buck mixed with NZW/Cali doe was slightly better, but still small shoulders. The kits did have decent rumps, though. I held onto two of them for possible breeding purposes, but at 8 months one was 6.5 lbs. The other, at 6.5 months was only 6 lbs. They dressed out nicely, though, because of their maturity... I think you're probably fine, even if they are still growing. Your buck, since he is not a Flemish mix, might help give the kits a better growout rate at the very least. The steel doe is very pretty, BTW.