Hi Warren, thank you for your comment. The following is not an advice. I understand the complexity that you talk about, this is also what motivates me to write the article, but personally I wouldn't take taxes too lightly. If it's a nightmare, it's unfortunately because you made it a nightmare, and I'm not sure this will be a good excuse.
I think you should try a tool like CoinTracking (mentioned in the article). You can import from many sources, or you can manually input the list of your transactions (currency/quantity in, currency/quantity out, and date.) The tool can calculate the value in USD at the time of each transaction and, as I mentioned, it can also calculate taxes with different strategies.
As always, I also recommend to talk to someone qualified to give you the right advise.