Jinsan:
I’m glad you understand that the_excerpt
doesn’t strip html if there is an explicity excerpt written. It only does so if there is no explicit excerpt. Like using the <!--more-->
quicktag.
Just so you understand, because I faced the exact same problem, if the_excerpt were to grab the first 120 words (default) of the post, it would grab an open <p>
but not the closing one. And who knows where it might cut off, leaving more open tags unclosed. To get around breaking validation, the non-explicit excerpt strips the tags.
When I want an image in the excerpt, I have it set up in an explicitly written excerpt with the graphic in place. This also allows me to customize the look of the excerpt.
Where I don’t have an image, and it is all text, I’m not worried and let that go. I have hundreds of posts to deal with, too, so I had to make choices and compromises.
If you already have a graphic in the top section of your posts which the non-explicit excerpt will grab, you have to take into consideration the size of the graphic so it doesn’t distort the design of your excerpt. I found that some images were tall and my text was too brief, so there was a lot of blank space compared to the height of the excerpt container. Finding the balance was a challenge.
Dealing with the bugs in MSIE and a couple of other browsers, having the “excerpt” container featuring an image not be pushed over and around by the next post excerpt was a chore and I ended up having to use the clearfix
fix from https://www.positioniseverything.net/ in order to get it to work.
I hope that excerpt_reloaded or whatever plugin you find will overcome these challenges. I just went through and added photos and explicit excerpts to my most important past articles, and then work to fix it from here on out.