5 Star Upgrade Poll R4 or R5

bazingamp

I am just about to finish Chapter 5 100%
Need to decide on next upgrade.
I only have 7 Tier 2 Alpha so I can only take R3 to R4 or R4 to R5 for some time.
Here is my roster

bazingamp

Correction on 2nd option 5 * UnAwakened Corvus upgrade to R5