I've changed the heading for the final section from Precautions to Drawbacks. I think that's a more accurate reflection of what's in that section.

For the first item in the list I've changed the word 'feature' to 'mixin'. Nowhere else on this page refers to mixins as features.

I've added a middle item to the list that discusses the problem of figuring out where properties come from when using mixins. That seems worthy of a separate point to me, though it does overlap a little with the previous item. I've removed the words 'and for debugging' from that first item as I think this is what it was alluding to.

For the final item I've just changed the punctuation.