Upgrading units to 5*

I have enough feathers to upgrade someone to 5* and i have some indesicion in that regard cause i have some good units to bring up and other that i like as characters and want them at 5*. Arena is not my main focus right now cause i want to have at least some decent merged units before trying to climb to Tier 20 (Even if i reached it once without even knowing how) as my best merged units are at +2 max (BK,Lyon who'll be +3 soon with the revival of his GHB and +Spd -Res Ephraim). Anyway the units are the following:

Red:
+Atk -Res Hana (She'll inherit a Firesweep Sword+ from a bad IV 4* Soleil thati found)

+Spd -Res Morgan (M) (I have 7 Red Mages at 5* in Arvis, Julius, Canas, Lyon, Sanaki and both Tharja and her Bride alt but Morgan is a nice addition)

Blue:
+Spd -Res Shigure (The only other blue flier i have is Valter and Shigure is hella fast)

+Atk -HP Cordelia (Mainly 2 reasons: First, she'smygorgeouswifeshutup. Second, she's one of the most amazing fliers in the game. I have a bad IV Roderick that will be brought up to inherit the FsLance to her)

Green:
+Atk -Res Raven (Although i already brought up Linus to 5* since they have similar stats, Raven seems really powerful)

+Atk -Spd Cherche (She's really powerful from what i've seen around. She needs just a Brave Axe+ and a decend C slot and she should be ready)

Colorless:
Neutral Kaze (He's a very good unit and i could make good use of him as a colorless magic tank since i have a -Res H!Sakura)

+Spd -Def Felicia (Same reasons as Kaze)

+Spd -Res Leon (Having another Archer is never bad imo.I have 4 Archers at 5* as of right now: F!Takumi, Klein (he'll get some merges soon, NY!Corrin and B!Lyn. So i think a fifth might help)