This is awesome!
Love it when someone opens a blog in something they either have experience in or are genuinely passionate about.
I would use the categories i mention above and do your own research and find the plugins the best suit your needs. But, i will venture to say, you will end up using many of the ones i mention there.
On the other hand and, since you mention you will be focusing more on building an authority website on a niche you´re experienced in, to start searching and opening random blogs and start evaluating their blog post layouts, designs, and formatting.
Just do random searches on Google using several high-competitive keywords and open the top 5 or 10 results from SERP and start taking screenshots of what i like to call "Blog Post Features". This is something that has helped me lot with how i would like my blog post to look like or how i present them to my audience.
By doing this, I was able to define many graphical and visual elements i need to add to my blog posts.
Stuff like different types of "boxes" that, not only help to break down the big wall of text, but also bring the post to life!
Boxes like quotation boxes, summary, tips, advice, specific stats (i really love these ones

) that supports a comment or a fact, among others.
By using this your content readability and engagement will dramatically improve making it more appealing to the readers.
I remember recently reading a quote in a video course i was watching. I don´t remember if it was on Ahrefs on Brian Dean´s but the message stuck with me as I believe it summarizes how a blog post should be built.
This is not the exact quotation message but it goes something like this...
SPOT ON!
Wish you all the best and would like to see you opening a journey thread. I would definitely follow that
Cheers!