Q: Transitioning from iPhoto to Photos in Yosemite.

Notes on Migrating an iPhoto Library from iPhoto to Photos for Mac

How Photos handles content and metadata from iPhoto and Aperture - Apple Support

And I suggest that you get up to date with OS X 10.11 and Photos 1.1 - there are many fixes and improvements

as to editing - Photos is much better - you may have to add additional adjustments - in the edit window click on adjustments and then on Add and add the ones you want - there are more than iPhoto and they are more capable

and as to this

Plus, when I thought I was setting up a new album, I find that instead I've got a "file" instead, etc., etc.

I have no idea - you create a new album under the file menu ==> new album - the only way to create a "new file" with Photos is to export photos from it (file menu ==> export) so you need to give us details and contest

see Writing an effective Apple Support Communities question

We can not see you and can  not help with abstract issues - you need to ask specific questions and provide details

for example adjust and enhance are default edit entries that are there all the time so somehow you are looking in the wrong place

TO edit a photos you double click on it to enlarge it and then click on edit

you also should always read the help topics and take the help overview for new programs

From Photos help on editing

You can use the Photos editing tools to easily make simple changes to your photos, such as rotating them or cropping them to get the best framing.

When you change a photo, Photos keeps the original so you can always undo your changes and revert to the original look.

Changes you make to a photo appear everywhere the photo appears in your library—every album, project, and so on. If you want to give a photo a unique look that appears in one version of the photo, first duplicate the photo and work on the copy.

Open

LN

you are welcome

LN

Moments in Photos are the new Events, i.e. groupings of photos sorted by date taken.

When the iPhoto Library was first migrated to Photos there is a folder created in the sidebar titled iPhoto Events and all migrated iPhoto Events (which are now Moments) are represented by an album in that folder. To open the sidebar if it's not already open use the Option+Command+S key combination.

NOTE: It's been reported by several users that if the Event albums are moved out of the iPhoto Library folder in the sidebar they may disappear.  It's not widespread but several users have reported that issue.  Therefore, if you want to assure that you keep those Event albums don't move them outside the iPhoto Events folder.

There's a way to simulate events in Photos.

When new photos are imported into the Photos library go to the Last Import smart album, select all the photos and use the File ➙ New Album menu option or use the key combination Command+N.  Name it as desired.  It will appear just above the iPhoto Events folder where you can drag it into the iPhoto Events folder

 

When you click on the iPhoto Events folder you'll get a simulated iPhoto Events window.

With Photos 2 that comes with El Capitan albums and smart albums can be sorted by Title, by Date with oldest first and by Date with newest first and there are a number of other features added that were missing from Photos 1.

Tell Apple what missing features you'd like restored or new features added in Photos via Apple-Photos Feedback.