Ok, so in case anyone out there is interested, I thought I'd share my experience with having a dress secure at the bottom.
The super strong velcro is secure, and it's supported by two bra-style hooks on either side. I have no fears on the ice.
However, one needs to bear in mind that the bodice needs to be super stretchy to get over the shoulders. Granted, the choice we made in the crysal pattern could have been much better, but as it turns out we sacrificed a majority of the stretch when we crystalled things up. The dresses look great, but now are a beast to get on (we have to help each other get our arms in and the dress over the head), and we lose a significant number of crystals in the putting on/taking off process. Of course our coach sprung for real swarovski crystals (from the teams coffers), so we do a throrough sweep of the locker room after each dressing event, and will need to do a re-crystalling session before the next competition. It's a pain in the bum.
A back zip would have been a much more practical solution on our case, and I noted that a lot of teams'dresses had that feature.
I'm not sure I'd write off the bottom entry design quite yet, but I would take into serious consideration the planned crystal design so that maximum stretch-ability remains in the fabric.