Here’s a vote for Adobe InDesign. I haven’t used it myself, but I used its predecessor Adobe PageMaker back in high school when I got sucked into helping with the yearbook and the newspaper. It’s basically a WYSIWYG layout editor. Text boxes, picture boxes, reflow of columns etc. Probably a good balance of features and learning curve. I know you can get the cloud versions for a few bucks a month now. Or there’s always other ways to obtain Adobe products…
You may also want to look into Scribus.
I should also mention I’ve only ever found layout editors good for the actual layout. As for content creation, MS Word is still my go to program. I haven’t found anything else that’s as good at helping to find those odd typos, grammatical mistakes etc that look rather embarrassing later. Type it in Word, strip the formatting, dump the raw text into a layout editor and Bob's your uncle.