My humble attempt.
First of all, I'd like to say that I really admire your work in the main SO site. I learned a lot from your answers. It's an honour to have a SO fellow user here. Make yourself at home, I really hope you enjoy this community.
Please, don't take my next lines personal. It's just some humble thoughts about the way I see this specific situation. And I'd like to share them.
IMHO TeX.sx behaves quite differently from other SO sites. We don't have for example the incoming traffic that StackOverflow has, neither too much offtopic questions. Jeff Attwood once said that no one would come here by accident, since this community is highly specific and technical. Since the traffic is slow, we can better deal with everything, say, a flagged post, a "poor" answer, an offtopic thread, and so on. I think that this community is very friendly, that is, everybody is really eager to help, to make knowledge better.
A quick overview to spot the difference: the first
101k rep user in SO has downvoted 857 posts; our
101k user has downvoted only 13.
Since every site is community-driven, we try to adapt things to our reality and not the other way around. Our methods would probably not work in other sites, say Math.SX or Spanish.SX. Sometimes, when I hear the words "SE policy" said in the wild, the walking hammers from The Wall come to my mind. Don't get this wrong, but I feel it sounds like an imposition: share it fairly but don't take a slice of my pie. I prefer to look at the SE policy as an inspiration for communities to work with a predefined set of suggestions and, as time goes by, work on their own methods, adapted to their own reality.
Now, back to the editing question.
IMHO your suggestions were valid - even Joseph mentioned he edited some questions in the same line in the past. But, at the risk of sounding unfair, I think the ultimate final decision lies with the author. Even though I think posts should be made clear - a nice formatting or proper spelling - I think we need to respect the author's decision on keeping things as they are.
I see the SE network as an awesome Q&A knowledge base, a new tendency. But I fear that people misunderstand the real concept and see threads as collaborative wiki. If it's a wiki, everything is fine, because you are collaboratively editing stuff. The Q&A model is based on people asking and answering questions. The site footer gives us a hint:
user contributions licensed under cc-wiki with attribution required
If we take a closer look on these links, we find the following statement:
Attribution - You must attribute the work in the manner specified by the author or licensor (but not in any way that suggests that they endorse you or your use of the work).
When we edit things from other users, we are signing a risky contract: we are somehow influencing the author's contribution - for better or for worse. But note that it's up to the author to decide if the modifications to his/her answer should really take place.
Of course, one might say that some modifications are towards improving spelling and grammar. Again, I think they are valid, but we can't impose these changes if the user explicitly rejects it. A silly example: we Brazilians are fond of commas - don't quote me on that. Portuguese usually has way longer sentences than their English counterparts, so we use a lot of commas. Sometimes, when I write in English - my poor English - I tend to add commas as my heart desires. Everybody can go and edit my posts - "The number of commas is too damn high!". Let's say I want to fight for my commas, so I rollback the edits. Am I wrong for rolling back a post to a previous state? I don't think so, even if the reasons for the edit are valid. The rollback feature exists for a reason, and I think the author has the right to take whatever decision on his/her own answers, no matter if there are valid arguments to support the edits.
The same line of thought is for deleted answers. Spoiler alert: 10k+ users can see deleted answers. Let's say I have a very nice answer with 10+ upvotes, and for some reason, I decide to delete it. Someone might say, "the answer is very good, let's undelete it for a greater good". Even if the reason is noble, I still think it's the author decision. It's a pretty "aggressive" way of trying to make things better.
Again, I believe your edits were very good, but it's up to the author to decide if the changes should take effect. I really enjoy reading Barbara's answers, and I always learn from her TeX expertise, besides of course the proper spelling and grammar. People that already know her style rollback edits just to antecipate the inevitable - she'd rollback the question anyway.
:) And she has the right to do it, after all, it's her contribution.
When we edit posts, we make sure to leave a note to the author of what we did - we already have a set of predefined text building blocks. It's a way to establish a good relationship with our fellow users.
Don't take the rejected edits too seriously. Barbara is a great person - I really hope to meet her in person someday in a TUG conference and lure her to sign my TeXbook
:) - and the lowercases are there for a reason. And I must confess, seeing one of Barbara's answer with the proper capitalization gives me shivers, "Jesus Christ, the AMS has spoken!"
Anyway, I hope you consider rejoining this community in the future.