ignatzatsonic,I wondered about the same question myself, when I was setting up my SSD.
And upon some reading found out that with modern SSDs we don't need to keep an unallocated space just for OP, the drive is as happy with free space in a partitioned environment.
For you and me, this doesn't matter as we can manage our PCs, but for computer novices/regular users setting up OP might help in the long run.
I see no benefit in having a separate partition for programs. If you have to reinstall the OS you will have to reinstall the applications as well, at least most of them. Added complexity for no tangible benefit.
Why have separate pagefiles on C:, D:, and E: drives? There is some theoretical benefit in having pagefiles on separate physical drives but probably not enough to notice. But in this case separate partitions are not the next best thing to separate physical drives. This will impair performance, not improve it.
My recommendation regarding multiple partitions:
Create as many partitions as you need, but no more.
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