Final thoughts: If I don’t set my blog page as the Posts Page in
WordPress > Settings > Reading
then things seem to work OK from a layout standpoint. Not sure what other implications there might be, but at least this aspect seems to be working for now.
More info: I created a new page and called it “Blog.” When creating the page, it let me choose the Blog Template. I was able to set the style to Large Image and it worked. Once I set that page as the Posts Page under Settings > Reading, however, the Blog Template option under Page Appearance disappeared and the layout reverted to the default.
I’ll also note that in reviewing the documentation, it says to pick the Blog Template under Page Attributes. My page is not displaying the standard template selector under the Page Attributes section on my posts page.