MacOS – Does using albums to combine events keep the events intact

Photos need to be part of events; deleting a photo from an event deletes the photo from your Photo Library (unlike albums where deleting the photo just removes it from the album). If I was you I'd create a 'One-Off' or 'Photos I like' event.

You could create a big event for everything you don't want to be in its own event folder. This should let the Events feature be used for what it's designed for - organising your photos by significant dates. If Events seems like too much hassle then you can just ignore them all together, make your own albums and organise them manually.

Personally I just use events to find photos from 'the picnic' or 'that time we went to the airport', I don't bother organising or sorting my events.

Another option would be to get iPhoto Library Manager:

iPhoto Library Manager allows you to organize your photos among multiple iPhoto libraries, rather than having to store all of your photos in one giant library.

iPhoto Library Manager lets you easily create and keep track of multiple iPhoto libraries, but that's only the beginning. It also has the ability to copy your photos from one library to another, while keeping track of photo metadata that is normally lost when exporting from one library and importing into another.

Titles, dates, descriptions, keywords, ratings, faces, and place information are all transferred along with the photos, ensuring that you keep all that information you spent hours entering into iPhoto. iPhoto Library Manager also reconstructs events and albums with the same photos as they had in the library they came from, as well as retaining both the edited and original copies of each photo. You can split up a large library into multiple smaller libraries, merge entire libraries together into a big one, and much more!