I totally understand your point, and I'll refer you back to what I think is the more significant part of my post:
It's not about stacking the "best" decks, it's about building a game that looks like it will be enjoyable at the time. If a randomiser gave you a setup that you just weren't feeling in the mood to play would you still go ahead and spend your time on it, or would you randomise again? Or would you maybe think "that setup is okay but I feel like playing Tempest today so I'll just switch one of the other heroes out"? It's been far too long since I was available to G+ but that was always the way it went down, basically using the randomiser to initially set the game up but then tweaking a little bit here and there if needed until it felt right for everybody.
I'm semi-random in that I don't use a randomiser but I also don't consider what particular team ought to be pitted against any given villain. In group games we randomly shuffle a villain into play then just pull whatever we fancy from the box and see what happens; when there are a lot of new players at the table I let them choose first, then I grab either a support hero or someone that I think will be particularly useful against the villain in case we start to flounder and the game stops being fun for them (all bets are off in subsequent games though). On the occasions that I solo I just go with whatever I feel like at the time, which is the more holistic approach I was getting at earlier; do I fancy a game with Visionary/Parse and a couple of others going up against Miss Information? Do I want to play AZ, Bunker and AN other against Akash Bhuta? Or maybe just a damage-centric beatdown on somebody? These are the kind of games that we don't indulge in during group play but are still a valid part of what Sentinels has to offer. Some villains just have a smaller spectrum of heroes that make the game 'work' than others.
All in all the great thing about this game, mentioned so many times before, is that there is something for everyone here and nobody has to like all of what it has to offer all of the time