I think you just might be trying to fit a bit too much in one deck. UGs, Sancts, Blessings, Pegasi, Fahrenheit,
and Seraphs?!? I feel like too often there will be a bad draw. I suggest replacing Fahrenheit with short sword, although that is just me. Will test it later.
edit: testing with -1 Seraph, otherwise same as OP.
first game: Dune Scorp ai3, 9ttw. Had Sancts and UGs held in hand. 0 RT used by opponent.
Second game: Pharaoh ai3 11ttw. Had UGs held in hand, with 25 Fire quanta from Light Pends. Tons of Blessings on the 1 Pegasi I drew. 0 RT used by opponent.
3rd game: Entropy/Death Ai3, 10ttw. Was able to play everything, all he did was mutate the 12 attack Pegasus into an Abomination and BE'd my first UG. Slowed me down by only 1 turn.
4th game: Timebow ai3. 11ttL. Wasn't able to play anything. Early Black Hole followed by a deflag on my only light pend, with 2 air pillars being my only quanta for the rest of the game, led to an easy win for the ai. He then stole my 2nd UG. GG
.
5th game: Timebow ai3 rematch. 12ttl. Was able to play everything, but Maxwell killed Pegasi, and Earth Quake combined with Steal and Deflag just destroyed all my Permanents. One Sanctuary wasn't enough to defend against his army he had at around 8-10turns.
Conclusions after early testing:
RT just destroys this. Easy to Deny.