Pias energy generation is not as strong as Saheelis, and her way of spending it is not as flexible nor as explosive
That means some X-spells become terrible Cascade hits unless they have a specific reason to be in the deck

Aang's Journey Brought Back Energybending Drannith Magistrate Zuko's Exile Empty City Ruse Aang, the Last Airbender Lita, Mechanical Engineer Aang's Iceberg Release to Memory Airbender Ascension Scout's Warning Airbender's Reversal Teferi's Protection Airbending Lesson Three Dreams Appa, Loyal Sky Bison Agent of Treachery Appa, Steadfast Guardian Bribery Avatar Enthusiasts Clone Avatar's Wrath Clone Legion Compassionate Healer Force of Negation Curious Farm Animals Imprisoned in the Moon Destined Confrontation Intruder Alarm Earth Kingdom Jailer Mystic Remora Earth Kingdom Protectors Prosperity Enter the Avatar State Sakashima of a Thousand Faces Fancy Footwork Standstill Gather the White Lotus Training Grounds Glider Kids Visions of Beyond Glider Staff Black Sun's Zenith Hakoda, Selfless Commander Bloodchief Ascension Invasion Reinforcements Cruel Tutor Jeong Jeong's Deserters Noxious Gearhulk Kyoshi Warriors Blasphemous Act Avatar Yangchen (The Legend of Yangchen // Avatar Yangchen) The Legend of Yangchen (The Legend of Yangchen // Avatar Yangchen) Diaochan, Artful Beauty Master Piandao Dockside Extortionist Momo, Friendly Flier Fervor Momo, Playful Pet Humble Defector Path to Redemption Insurrection Rabaroo Troop Lightning Bolt Razor Rings Mirrorwing Dragon Sandbenders' Storm Rending Volley South Pole Voyager Searing Blood Southern Air Temple Shattering Spree Suki, Courageous Rescuer Volcanic Torrent Team Avatar Warstorm Surge United Front Beastmaster Ascension Vengeful Villagers Elemental Bond Water Tribe Captain The Great Henge Water Tribe Rallier Heartbeat of Spring Yip Yip

It has a good collection of keywords, but a 2/2 for 3 mana is far too small to be able to take full advantage of them
As with R/W, this broad overlap makes it easy to lock in U/B at the start of the draft and then use its generic graveyard manipulation to set up whatever third color comes your way
She keeps the auto attach equipment ability and overall this is a pretty solid curve out in a red deck