I like The lore surrounding Avernus, Tieflings and cosmology of DnD
Well, Going back to my recommendations above - Erin M. Evans' Brimstone Angels series (Six books in total, One is part of the 5th Edition reboot series 'The Sundering') focuses heavily on a pair of Tiefling sisters as they navigate their place in the world, an infernal pact and the attention of many, many powerful beings in the Hells.
While not specifically dealing with Avernus, Malbolge is a recurring backdrop as Glasya, Archduchess of the Sixth Hell and daughter of Asmodeus, is a constantly lurking power.
The series varies in theme, focusing on telling a story about coming of age, responsibility and the weight of power.
The only reason I didn't give it a lengthy write up and praise above was that when I was typing everything up, I had a headache and wanted to lay down.
Elsewise, for a Faerun-grounded Planar journey, you're in an bit of an awkward spot.
There's three series that immediately come to mind, but they have the 'baggage' of being sequels.
So - First, there's the War of the Spider Queen. A six book series in which many of the authors mentioned above each took a single novel and had to weave the narrative towards a conclusive end. Some characters suffer for their interpretations under different authors, others flourish - But all the same, it could be considered a full adventure campaign with drow characters, starting grounded with visiting other Drow cities in the Underdark before moving into the Abyss itself to try to learn why Lolth has gone silent.
Two spin-off series come from the conclusion of War of the Spider Queen - The Lady Penitent Trilogy, by Lisa Smedman, which explores elements of the Drow Pantheon as Lolth attempts to kill off her divine children and consolidate power over the fate of all drow and their very souls.
The other, The Empyrean Odyssey trilogy, by Thomas M. Reid, follows Aliiza, a half-fiend who was involved in the War of the Spider Queen, as she tries to escape Kaanyr Vhok, the lord of the Scoured Legion. Her escape will take her to the House of the Triad in Celestia, one of the heavenly Planes in the D&D Cosmology, wherein she's given the opportunity to fight against her nature and try to find redemption.
