Jack, I used Canvas back in the late 90's maybe early 00's (hard to remember, exactly). Anyway, I was so happy to find Pages back when it first appeared, it was much more intuitive, didn't crash, etc. Now that's it's only $20 I don't see any point in trying to keep Canvas running. Frankly, I'm surprised it's still being offered for sale.
I still remember creating multi-page, half-sized booklets with Canvas trying to get the text to "bleed/flow' from one page to the next section and keep the page numbers accurate. Ended up making a paper 'model' so I could figure it out!!!
I doubt that Pages can read old Canvas files and maintain the formatting/layout/etc. but Pages is a very capable little app and well worth the original $75 for the whole iWork suite.
Of course, the biggest drawback in most of the Mac App Store method is that there is no "try-before-you-buy' option.
OTOH, $20 is a lots less to lose than several hundred fro other page layout apps.
BTW, Pages has two basic 'modes'; "Word processing" and "Page Layout." I tend to use the blank page "Page Layout" mode more than anything else since it offers a completely blank 'canvas' on which anything can be done; text where you want it, images, graphics, masks, etc. OTOH, I know some who start with a WP sample and modify as needed. You might message
Richard, I know he uses Pages for a monthly newsletter. And there are several web sites with lots of help and suggestions. BTW, be sure to mention my name, should you purchase Pages, I get a 3.5% commission!