I see Embercleave as a way to trim the narrow red 1 drops.
I've removed Jackal Pup, Falkenrath Gorger and Firedrinker Satyr.
I've added Embercleave, SoulScar Mage to try to reduce the number of parasitic one drops to allow the red deck to be more a bit more midrange. (Similar to standard Ramnup red than mono red in modern/ legacy)
I love this btw. However I like Firedrinker Satyr in the decks you're describing, but cutting Pup and Gorger is A+ in my book.
While this is a cool card I have a hard time seeing how this is better than other options in your aggro deck. It requires the game to be going “as planned.” If they wrath or kill off a couple of your dudes this does nothing to get you back in the game, yet that is exactly what I need my non-1-3cc creatures to do for me.