I'm only really thinking of closing the LLC if it truly makes things more complex than having a Sole Proprietorship. @SeattleCPA mentioned that owning a business makes taxes complex,<snip>
That's true. With a business, you have to have an accounting system. Issue 1099s. Maybe do W-2s if you've got employees. You may need to deal with sales taxes. File in multiple jurisdictions. You'll probably have assets to depreciate. Lots and lots of stuff that is way more complicated that someone with a W-2.
then later agreed that an LLC is no more complex than a Sole Proprietorship, so I may leave it after all.
Unless it makes an election to use another classification--like an S corporation classification--a simple member LLC that operates a trade or business is disregarded. Thus it *is* a sole proprietorship. A sole proprietorship is way easier to handle than an S corporation though. That was the point, I think, of the comment you reference. Consider the page counts of the tax forms. A Schedule C form used to report a sole proprietor's activity to the IRS is basically two pages. The 1120S form used to report an S corporation's activity is at least six pages and probably longer.
Either way, I'm getting the impression that the best way of learning here is to meticulously compare professionally-prepared tax documentation with my own DIY efforts as a sort of deliberate practice.
For what it's worth, if I was looking at the different areas of accounting and finance that might help me with better managing and understanding my business? Or my finances? Tax would be way down the list.
I'd recommend a small business really learn the nuts and bolts of bookkeeping and general accounting first. That'll mean she or he has good timely data for managing the business. And then after that, and building on that data, I'd learn about how to do financial analysis (so capital expenditure analysis stuff like IRR calculations and NPV calculations) so I could optimize stuff in my business.
In college, the above subjects get covered in the first two "principles of accounting" classes and then the 300-level corporate finance class. Surely there are online versions of these things. Probably free even?