This is really one of those sticky subjects. On the one hand, I do understand the desire to be able to use a pet based solely on looks, without having to go "Okay, am I gimping my DPS by bring this pet along?" But on the other, I have always loved that unique feel to pet's, pet's bringing a different flavor, or a different approach.
Yep, same for me. I believe the devs feel the same way, or they would have completely normalised pets years ago.
Would having beast mastery have meant HAVING to use an exotic? To an extent, yes. But it's no more of an extent that people HAVE to use a wolf now, or HAVE to use a devilsaur.
The devs (through GC) have stated that it strikes them as being wrong for BM to have a more limited pool of pets to choose from than MM and SV. There's also the fact that you can't get exotics until level 60, so a lot of hunters are going to object to being told that the pet they have used to get them to their 51 point talent is no longer a good choice. So if
they have BM-only pet families at all, then they need to be optional. However, I personally wouldn't mind at all if they just abandoned the idea of exotic pet families altogether in favour of a "hunter must have Beast Mastery talent" prerequisite on some pet talents.
The min/maxers are GOING to min/max no matter what you do, even if that percentage is just by .5. Blizzard has said as much themselves, but then go on to blithely state "But we feel like people are more likely to go for diferent pets if we have it within that .5%!" which is mostly untrue. The people who are just worried about the 'best' will continue using the best, and the people who don't care about that kind of thing will continue to use whatever. It was always, as is often the case with Blizzard, just a lame excuse meant to feed the masses some shlock that sounded good.
I think you're making a mistake here in dividing people into just two categories. My experience is that people care about min/maxing to different degrees. Some have a favoured spec that they will stick with regardless of what theorycrafting says. Some will change specs at the drop of a hat, for whatever the current flavour of the month happens to be. However, the "casual raiders" in DoA tend to mostly fall into the category where we will pay attention to the theorycrafting, but only think about switching when the discrepancies become huge, with the definition of "huge" varying for each raider (usually relating to how attached they are to their current spec, how easily they learn new ways of playing and much they care about being as good as they can be in the time they have available for the game). So the closer Blizz can get the balance between specs (and pets in the case of hunters) the smaller the pool of people that feel obliged to change. While Blizzard rightly acknowledge they will never reduce the size of that pool to zero, that's no reason to throw up their hands and give up on making it as small as possible.
I understand the philosophy, I understand the ideology, but I don't understand the methodology. The wolf has been the clear best pet for a while now, and in most cases, not by a little. They speak a big game, and yet when it comes time to put up or shut up, we get silence from them. It would be a simple matter to balance out the wolf, or give furious howl the thunderstomp treatment, but as with many things, Blizzard is content to let something be blatantly better. I'd be a lot more inclined to believe their crap about balance if they ever actually did some balancing.
Changing Furious Howl would need a lot more design work than changing Thunderstomp did. If they just took it away across the board, then they risk nerfing hunters more than they intend. If they added it back in as a Ferocity talent, then they risk already competitive pets like Devilsaurs, Cats, Raptor and Spirit Beasts becoming overpowered, as well as having to consider the PvP implications. So, if I was them, I would be suitably cautious about messing with it as well. With entire DPS specs still not being PvE viable, having hunters overly dependent on a single pet family would probably be a fair way down the list of "things to fix".