Personally, I would make multiple ADRs at an adults only resteraunt. DH and I have no children, and while I expect them at Disney, I do need a break from being around them all day long. The energry that little children put out is overwhelming, sometimes you just need a breather. I don't always want to go back to the hotel room for a break, it would be nice to have a sit down place to do that also. Pleasure Island might have places that are 18and over, but they're not sit down resteraunts.
I do think a better solution would be to have true lounges attached to resteraunts where under 21 is not allowed. No if ands or buts. This is common in every city that I've been to, there's even those little signs about 21 and under not allowed in because, oh, it's the law. In the area we live, most of them all have a full menu available from the sit down area also to order from in the lounge. Whenever we go out, we always request to sit in the lounge, specificially because we've had screaming children in our ears way to many times. But then again, one has to wonder why a two year old is to dinner at 9pm anyway.
V&A is not an adults only place, there's not a kids menu, so it should be a hint to parents to leave them with a babysitter, but not everyone gets the hint.
And flame on.