[Anubis]

SSDs should maintain relatively steady performance regardless of how much data is stored on them. Magnetic drives show significantly reduced performance at near-capacity due to the moving components within them. The performance of an SSD will, however, degrade over time as the cells are rewritten many times. For this reason I personally avoid any excess caching and space-wasting files, such as a hibernation and pagefile.

For reference, I believe the Z77 chipset in the selected motherboard also supports Intel SRT, which is useful when you have a (inexpensive) SSD that's 64GB or smaller. Instead of using the SSD as the primary drive, the Intel RST software will use the SSD to cache files that are commonly used from another magnetic drive. Not as fast, but still a bit snappier.

Something to keep in mind (especially when dealing with smaller size drives) is that while the SSD is marketed as 128GB, it has only about 119GB useable space. Though as you're going to be using additional drives as well, this won't be an issue at all.

Looks pretty good for a first build. Assembly shouldn't be too bad at all.