Brazen Atk/Spd Micaiah

Title. With Linus incoming with Brazen Atk Spd, I'm thinking of replacing the Defiant Atk 3 on my +Res/-Def Brash-Desp Micaiah with Brazen Atk/Spd, but I think it might not add enough useful doubles (only on the non-DC users between 26-30 speed) to warrant the use of such a valuable skill.

If not, what are some recommendations on whom I should use it on instead? I'm considering:
- Sealed Falchion/Vantage +Atk/-Res Lucina (haven't added Fury yet, can replace Vantage with a spare Shanna)
- Ardent Sacrifice/L&D/Desperation +Spd/-HP Quadelia (would replace L&D 3, may not be worth?)
- Vantage Camus, basic stuff.
- +Spd/-Res Siegbert, currently Death Blow and Desperation

Most of my good Heroes are on my page https://fireemblem.gamepress.gg/user/35571, but some may not be accurate as I haven't updated it in a while. I also have a majority of the 4* cast prior to the mass-demotion in various forms of merges and IVs, TT and GHB excluding Clive, and a few other random 5*s with sub-optimal IVs.