A lot of this is really good advice, so I'm just going to focus on a few differences between a Rec List and a Rec Blog. I've done both of them, and they have different strengths!
A single-person Rec Blog (a blog that only posts fic recs, one rec to a post) is great for long term reach. You can show off the widest variety of fics. It can slowly gain followers, and people can learn what you like and how it compares to what they like, allowing them to really start to trust your recs!
I find that it helps to have a set format for posts, and to provide more info than you would on a rec list - things like ratings/warnings, ships, a separate summary and comments section, etc.
A Rec List (one post with a bunch of fic links) is great for creating connections in reader's minds. If they know one authour, they can be introduced to other authours that share a positive quality - similar types of prose, the same types of kinks, a shared tendency to write 50 chapter epics, etc.
This means the fics should be carefully chosen. Just throwing up a bunch of fic you like is functional, but doesn't work to the format's strengths.
It's usually better to have shorter recs than a blog would, relying on an intro to get across the theme, along with general range of warnings, etc. The recs are mostly your reaction, with maybe a sentence hinting at the plot. Individual warnings are only necessary if a fic is exceptional - something like, "This one is darker than the others, with a bit of a horror vibe, but the sibling relationship [or whatever the list is themed around] is SO GOOD!"
Regularly posting rec lists can allow you to get many of the strengths of a rec blog - readers who have learned to trust your taste, possibilities to rec a wide variety of fic, etc. - while also keeping all the strengths of the lists. I've followed multiple people who did this, and they were all great!
Also, a Rec Blog that allows other people to submit, like I'm currently running, is slightly different, as well.
These are great for building a community. They allow for the longest lifespan, as long as you don't burn out - because you aren't the only one supplying them with fic. And they allow YOU to discover new fic!
Structure of posts should be even more formalized. More info is helpful, because people's ability to communicate what they like about a fic is going to vary wildly, and readers aren't going to learn the submitters' likes and dislikes in the same way they can for a single reccer. You have the highest chance of writers stumbling across their fic, so I STRONGLY suggest a policy of focusing only on the positives.
A final format is the Multi-Topic Rec List. I have a list I updated for almost a decade, until Tumblr stopped allowing me to edit posts that old. It was focused on a single character, with sections for specific tropes I love. I keep a link to it in my header and pinned post. Really fun to be reading a new fic and get all excited that you can add it to a specific section!
Great if you're not making recs frequently enough for regular lists/blog posts, and aren't looking for huge reach. It never got reblogged a lot, but it did get an outsized number of people sending me messages telling me how much they appreciated it, which is a very different and enjoyable experience!
Tagging the authour seems to be controversial, but I suggest no matter what format you choose. I also suggest wording things in a way that will feel good for authours to read. Recs are for you and other fans, but fandom works better when we're consistently building each other up, even when the other person isn't around.
Also, tagging the authour can expand your reach a LOT. Authours love reblogging posts complimenting their fic, which means their fans, people who presumably like similar fic to you, are exposed to your rec blog/list, and all the fic by other authours you think are equally good.
