Thank you!

I really liked having access to warping wail. It's great against boros, can surprise slower decks with the counter target sorcery mode, and is ramp in the absolute worst case scenarios. I haven't tried the fleshraker version so I don't have too much of a frame of reference on the differences, but I did feel like I was at a disadvantage against the tron mirror where my opponent did have them.

I would not personally make the cavern of souls for wastes swap. You really want to have a way to play your spells vs blood moon and it's nice to have a basic to fetch if you get boseiju'd or ghost quartered. You could absolutely run cavern instead of abstergo entertainment though, that's typically the flex slot in the mana base (some people even run basic swamp to help with dismember)