For the duration of the fight, creatures in the immediate area will not be visible to you (but they may still attack you if they wander too close). Keep in mind that other players will still be able to see you and attack you if you are eligible for player vs. player (PVP). Other players will also be able to view your pet battle in real time, including the pets involved as well as their health as the match progresses.
When it comes to Classic, Blizzard's goal is to provide an authentic Vanilla experience, but they also needed to come up with technology to handle many players at launch, which is similar to sharding. While the use of this technology will be limited to the first month following launch, many players are questioning this decision and wouldn't like to see layering in the game at all.
Different qualities aren't limited only to wild pets—many rare World drops and special non-wild companions have had their stats boosted. For example, the world-drop dragon whelps (Azure Whelpling, Crimson Whelpling, Dark Whelpling, and Emerald Whelpling) are of [rare] quality. Check your Pet Journal to see the color-coded rarity of your non-wild pets.
Well, I think, a “wall of of text” is not defined by the amount of characters. To create a wall of text you need two things: lots of characters, and lots of missing line breaks / paragraphs. I’m completely aware of that, and I’m always trying to section and format my texts in a manner that makes it usable for readers ;) I think the limit of 990 chars is not contributing to avoid walls of text. (It’s easy to build a a wall of text with only 500 chars, but I think you got what I mean…)
It was the experience of the game that brought pleasure and joy, and that's what a lot of us want again. Not the numbers. When I play Classic I want to go through the deadmines with people I like and overcome a challenge together and see myself become stronger as a result. I don't want to play Classic so I can say "booyah! That number is exactly the same as it was 13 years ago!"