I am not a writer, but I have a different suggestion similar to yours.
Read those rules and such listed by others especially writers. Then pick and choose which ones fit your individual style of writing.
Add the selected rules to your own individual list.
Then review your individual list adjusting it as your understanding and knowledge grows.
This has always been my position. Since I'm not obligated to use a particular style guide, I bristle whenever I'm told that "ze must do things this way because such-and-such style guide dictates such". Style guides aren't even an optional list of writing choices, they're merely 'acceptance guidelines' for submitting your works to specialized publishing houses. If you're writing for newspapers, you use one. If you write non-fiction textbooks, you use another. If you submit works to publisher A you use a separate one, and if it's rejected, you then change the entire text to match another style guide to submit it someone else. They don't so much list 'what's correct' as they list what one particular group requires.
That said, Ross is correct. If you're a new writer, it's easiest to simply pick a style guide and then you can essentially ignore all the various guidelines and follow the dictates of that one style guide. Essentially, their a short cut to understanding the strictures of English. They TELL YOU what to do, so there's no question how to handle certain situations.
The main problem 'that experienced writers keep telling me' is that, in writing fiction, many of those rules don't fit as the style guides weren't written for fiction. There are few references in any of these style guides on the proper use of the em-dash or ellipsis in dialogue (to denote interruptions or hanging pauses). If you never plan to use either, then sure, feel free to pick a style guide and follow it's dictates.
However, in exchange for a simplfied learning curve, you also lose the opportunity to learn new tools which can often help your writing.
Ross has a point, for newbie writers, picking a style guide makes sense as it eliminates the indecision phase. However, I was merely cautioning (not lecturing) that he should first ask authors he's editing for which style guide they follow before quoting a particular style guide. That was my only point: that if a writer hasn't selected a single style guide as a starting point, then limiting their choices based on that one source is misguided.
In short, if you're writing to be published, following a style guide makes a lot of sense, and you can churn through one book after another until the publisher finally selects one to publish. However, if you're not limited to a specific publisher, one you've gotten a feel for writing, I'd suggest that authors spread their wings and try out different techniques to discover which ones work for them, rather than following random dictates that don't really apply to them.
In short, style guides are a choice. You either elect to follow them, or you don't. Quoting them as a reference doesn't carry much weight, as they're no more 'correct' than is every other style guide.
That said, I'm sick of kicking this particular dead horse. I wasn't picking on Ross. Instead I was simply cautioning him about an over dependence on quoting style guides to unaffiliated authors. Each author should decide for themselves whether to use a style guide for themselves, and editors telling them they're wrong because they picked the wrong guide isn't helping them write.
I did recommend a style guide for authors — the Chicago Manual of Style. The reason is simple. It's what the publishing industry uses.
So since the goal is to be consistent, you might as well use what the traditional publishers use.
This is the long and short answer. If you want to pick a single guide (rather than struggling with each question individually), then go with the gold standard which makes it easier to eventually get published. But don't dictate what choice other authors make, because they might not have made the same decision you have.
@Ross at Play
Can you recommend a different starting point for NEW authors who want consistency in their grammar and punctuation? (with it taken as a given that fiction authors must relax some, or many, of their rules)
Since I've gone the 'no specific style guide' route, I tend to favor asking sites like Grammerly and Grammar Girl specific questions for the best options, rather than following what someone else decided to do. That way, you can make more informed decisions by understanding WHY one technique works better than others.