> Understanding emptiness
The other points are valid to me, this one belongs in the realm of metaphysics for me.
Buddha said a lot of good things IMHO, but very questionable stuff too. "Monasteries are allowed to own slaves, individual monks not." for example. If you mention that, Buddhists get uneasy and/or defensive.
There is a nice App called Buddha Quotes on F-Droid. I recommend to install it via Foxy Droid: