Interesting take on the Pharaoh Mummy deck. The Chimera is an interesting touch I haven't seen before. Same with the healing ability. However, I think it might just slow it down too much... usually the point of reverse timing mummies is to speed up the damage and the rate of getting Pharaoh's out, so why clog it up with healing and more Pharaoh's. You only need a two or three Pharaoh's to fill the board.
So if we were to keep the additional healing ability, you could drop the Pharaoh's add Mummy's switch Death Pendulums for Death pillars. Drop the Gravity Pendulum's and Chimera, toss in an Eternity, and a couple more SoRs.
So - 4 Gravity Pendulums - 1 Chimera - 2 Pharaoh's - 8 Death Pendulum's
+ 2 Mummies, +1 Eternity + 2 SoRs + 8 Death Pillars
33 Cards. Should make it more stable.