Oh okay! I'm... struggling with the layout of this, but maybe it's because I'm still very new to the system. So would Haunt, The Treasure's Call, and A Fearsome Blessing be viable choices since I'm at Sentimental 3?
After gaining a level in a Miraculous Arc, you get all the powers up to your Arc level. Since you have Sentimental 3, you get all the Sentimental powers except for Wish! Since you're also on Child of the Ash 0 (I think), you get all the Child of the Ash 0 powers.
Perks are a totally different thing from Arc powers. You have eight total Perk slots, but you don't start the game with all of them full: for now you get to pick any three you want, plus some level 1 Connection Perks to whichever PCs you think Taldin would know well by the start of the game. Once you complete a Quest, you get a new Perk—this is usually stuff like miraculous powers, Bonds, Connections, Skills, and so on.
Sentimental is an unusual arc in that its powers let you do cool stuff with what it calls your "Treasures". Page 545 of the PDF explains this further, but basically, you can get a lot of Treasures as Perks. Pages 441-445 of the PDF have some good suggestions for Perks for you—I'd suggest any two of Bond, Accessory, Connection, or "It's like a home to me" so you have more stuff to use your Arc powers on, plus a Bond, Affliction, or maybe a miraculous power to represent Taldin's inheritance.
Chuubo's... is surprisingly crunchy. I hope I haven't made it more confusing for you.