For the sake of argument, all edits are considered an improvement in this post. No matter how minor.
Since we consider edits an improvement, I feel free to say that they are a good thing. However, one can imagine that not all edits are equally grave. I would like to use the following example, some user notices that in some old post the word "their" is misspelled as "they're" and that there are no \$-signs around
Now an edit would certainly do that post good. I also believe that it should be done, because SE is not merely about people who have questions they want answered. SE also keeps in mind future visitors with similar problems (perhaps visitors that aren't even a part of the SE-community). It is therefore good practice to have everything looking/spelled/formatted/etc. as well as possible.
However these aren't the kind of things everyone needs to be notified of. Would it therefore be a good idea to give users (possibly only high-rep users) the option of editing a post without it being bumped to the front page?
To keep the peer review intact, users could be given the choice if they want to see all edits on the main page, or only "significant" ones.