This is the best post I’ve seen on passive income streams. I’m similar to you in that I worked in IBanking for a few years but wanted out. My approach is a little different, instead of starting with the CD’s, I’m trying to build up my net worth with riskier asset classes such as stocks and real estate to get the benefit of compounding. Then, as I approach my retirement year goal, I’ll start moving them into CD and bond ladders. In theory at least, it’s best to have the highest net worth just before retirement, then convert them to risk free passive income. You’re method is more patient and probably more practical than mine. I guess I’m willing to take more risks.
One of the most appealing options, particularly for millennials, would be #12 on your list (create a Blog/Youtube channel). The videos can be about anything that interests you, from your daily makeup routine (with affiliate links to the products you use), recipes (what you eat each day) or as you mention, instructional videos (again with affiliate links to the products you use). Once you gain a large following and viewership, you can earn via Adsense on YouTube.
You can select any of the above-mentioned, based on your interest, skill, and capability to generate a second income source. However, these are just to name a few, there exist multiple ways to generate a secondary income channel. You just need to identify the right one, which suits you the best. Remember there is no shortcut to success and you need to work hard to be successful and rich in the long run!
Portfolio income can come from multiple sources – interest/bond coupons, stock dividends, financial strategies including derivatives and capital growth.  Each offers some cash flow and some also offer potential capital gain with some risk from liquidity and volatile prices.  In this low-yield environment, many investors rely too heavily on cash flows and to pursue this are venturing further into riskier areas than they’d normally consider.