I totally get you concerns regarding debt: what if the tenant doesn't pay or they damage the property, or the water heater goes out, or there's a roof leak, or the furnace dies? You know what, if you are in this long enough all of that will happen. You need to have some money set aside to handle all of that, and it sounds like you do.
I listen to DR, his all debt is bad debt makes sense for someone who makes 50k a year, has 60k in credit card debt, 100k in student loan debt and 50k in car loans. Where i disagree with him is on the cash for rentals. Starting out, its very hard to acquire rentals without debt. As your portfolio grows and you age, you can then look to wind down the debt. When i do hit the FIRE button, I'd much rather have 10 paid off rentals than 30 financed at 80% LTV.