As far as your "recently altered files" question, Nick, this is simple. Create a Smartlist, and add this as the search criteria (you can of course add other criteria to limit the results to just music files, or just a certain genre, or whatever)...
[Date Modified]=<=90d
Where the 90d is 90 days. This one would limit the results of the smartlist to those files modified in the past 90 days. You could change this to 180d, or whatever other timeframe you'd like.
You can also use [Date Imported] instead of [Date Modified] to list those files based on when they were ingested into MC's database, rather than when they were last modified.
As an example, I have a View Scheme (I use them instead of Smartlists, but they work the same), with the following search:
[Media Type]=[Audio] [Date Modified]=<=60d ~sort=[Date Modified]-d
This will show all the Audio files in my library which were modified within the last 60 days, and it arranges them in order by the date they were modified with the most recently modified files on top.