NAS RAID1 GPT STORAGE/srv All Together

Hello, I’ve just upgraded my TO to NAS perk and wondering how to configure it. My idea was to set RAID on two disks (3TB one partition for RAID and 6TB two partitions first 3TB for RAID and second 3TB regular partition.

So now step by step.
I would activate both disks with GPT. No issue. Recent fdisk already supports it. Of course 3TB disk does not need to be GPT based, however I’d prefer as similar config as possible for both disks. Then create first partition covering whole 3TB disk.

And now the first question. What should be the type? Should be Linux RAID (hex 29) or regular Linux Filesystem?
Second disk, create two partitions, one 3TB for RAID, apply same type as above question and then create second partition as standard Linux Filesystem.

Next think should be to create /dev/md0. I have found a command somethere here in forum
mdadm --create --verbose /dev/md0 --level=mirror --raid-devices=2 /dev/sda1 /dev/sdb1
Now the second question. Having /dev/md0, Foris does not recognize the partition and does not offer in its STORAGE section setting /srv to be on RAID. Can or should I do it manually?

Final step would be to make averything persistent end mounted after boot. I can find in other posts:

And final question. Is still recomended to disable NCQ?