Is the other partition needed?
In the normal course and on an MBR setup, not strictly
, although if you ever have boot problems you'll be very glad it's there, since it's where the (Windows) recovery tools live. Occasionally it's also the active partition, why Windows can't be consistent I'm not sure, in that case leaving it off will require fixing boot issues after a restore.
On the other hand it's small, so including it has little penalty. Windows can be made to function without it, or even installed without, though feature updates are quite likely to re-create it by shrinking C to make space if you do waste the effort forcing the issue, at least, unless you have enough partitions defined Windows can't make a new one. Under which circumstances it finally proves it actually can
live in one partition on a BIOS/CSM - MBR system.
Also. If I were to clone this array to a single SSD would the system have enough info run without RAID (since it will be only one disk).
If you clone it to a non-raid disk, Windows will *usually* have drivers to run normally in AHCI mode, it's going the other direction that usually
causes issues (switching *to* RAID) if there are issues, usually you can set the controller to RAID mode regardless of not creating an array, boot & fix the situation. Alternatively using re-deploy (in the paid reflect version) will often sort such issues as may arise going either direction.
If you clone then such a clone will obviously still be an MBR disk, meaning you'll have to boot in CSM/BIOS mode rather than native UEFI, unless your motherboard has a strictly BIOS mode which hides that it's UEFI capable, Microsoft are either actively blocking or threatening to block future feature updates, so you'll ideally be wanting to convert to native UEFI boot.
Personally rather than cloning I'd image, then restore to a GPT disk & fix up booting in UEFI mode, as outlined in the Knowledgebase here
that does involve extra (but small) partitions ahead of the system one which are
required, I'd also stage the restore adjusting the properties (size) of the system (C) partition before dragging down the recovery partition after it, that way you can avoid wasted space at the end of the drive.