This.
Along with letting you assign ASIs freely they should also just add more possible choices for each Background. Maybe 4 possible Skills you can pick 2 of and let you pick from 3 possible Origin Feats.
Here's the great thing:
Tasha's Cauldron of Everything still exists and this sort of customization is part of the 5e ruleset. Did it make it into the 2024 Revised Core Rules? No. Have they forgotten that the Rules Expansions still exist? No. In fact, these two FR books say in many places "as detailed in
Mordenkainen Presents: Monsters of the Multiverse" or "see
Fizban's Treasury of Dragons" etc. Will there be a revised Rules Expansion at some point that consolidates 2014-2023 rules expansions and splatbooks' subclasses and species and other PC options? Probably -- I'm guessing that's what both the Arcane Subclasses and Updated Subclasses UAs are working towards, the next
X's Y of Everything. But just because something from
Tasha's was republished in a 2024 or 2025 rulebook doesn't mean that
Tasha's is now somehow "non-canon" and you should burn it in a funeral pyre. 2014-2023 material still exists to be used until they update that option in a 2024-onward book or explicitely say "Z feature is intended to replace W feature from earlier rulebooks" like they have with options such as
- Grave Domain > Death Domain;
- Undead Patron > Undying Patron;
- Choice of Human or Orc Species in the Rev-PHB > Half-Orc Race in the 2014-PHB;
- Choice of Humans, Elves, & Khoravar Species > Half-Elves in the 2014-PHB
...etc. I'd also note that people cried foul for lack of Drow as Monsters in the MM 2024, and they said they'd be in setting books because Dark Elves aren't by default evil and you can just customize the Cultist or Warlord or whatnot generic NPC statblocks for individual evil Drow just as you could use them for individual Humans or whatnot, but for FR, where evil Drow are a part of the assumed setting, there would be evil Drow in the bestiary. And voila, there are. I bring this up because of similar foul cry about Half-elves going away but the Khoravar are featured as their own species in next month's
Eberron: Forge of the Artificer, showing that it was never an intent to erase Half-elves so much as to avoid the messy eugenics-adjacent questions of how "crossbreeds" work in baseline D&D and leave that sort of question to be explored by a setting that explicitely set out to ask said questions (as Eberron does with the Khoravar's unique and separate culture despite its founders originating as Half-Human, Half-Elf individuals). But for a year there, you didn't have a one-to-one way to represent a Priestess of Lolth in Revised-5E, and even the suggested substitution was a bit lackluster. But that's in part because they still stand by that the 2014 splatbooks and the Expanded Rules from 2014-2023 are intended to be compatible with the 2024 Revised Core Rules. Even the Cleric and Wizard subclasses from the 2014 PHB that didn't make it into the 2024 PHB can and are used by people otherwise playing a 2024 Cleric or Wizard, and while there's a definite push to fill in the Wizard magic school gaps for whatever this 2026 Big Book of Character Options will be, Cleric is not nearly as rushed to update the Nature & Tempest Domains (mostly because Druid can fill the gaps for Nature Priests and Stormy Sea Priests with two of its 4 2024 subclasses).
But that's all to say, in the text of these two Forgotten Realms books, there's an enthusiastic attitude of "use these old books with the new ones." So follow suit and use the Custom Origin/Custom Lineage tool sets that have been published for 5E. They may not fit perfectly, but D&D is meant to be customized. They fit well enough that they're usable, while at some point, the older book's contents may be depricated enough that they're worth all updating in various new locations (hence Bladesinger, Circle of Stars, Warrior of Mercy, Knowledge Domain, etc).
