Although big textures can pretty fast fill your graphics card memory, the bottleneck is still processing them, hence it's usually the GPU and not the reloading of data.
Thats not true!
The GPUs (even midrange) are strong enough to process big textures, or even really big textures compared to the standard textures most games have, at almost no cost. When big textures really start to lower the FPS (I am talking of about 10 percent and more) the most common problem is that the Memory of the GPU is to small, so that textures have to be reloaded (if you are lucky from RAM and not the harddisk) and reprocessed (time consuming, especially for slower cards) over and over again instead of just using the ready textures to continue rendering frames (which takes almost the same time independent of the textures size).
Nvidia added a shader cache to their drivers recently, and it improved performance and removed the stutter/lag in open world games like Saints Row 3 and Skyrim for me.
As far as I know it wasnt a shader cache it was an improved storing of image data (textures) so that they need less space in the RAM of the GPU, because of better compression, so that the described stuff I mentioned above doesnt happen that often.
I hope it's not a CPU bottleneck. My CPU is still just fine for most new games, but it struggles on some older, single-thread games :/
For skyrim it could be a CPU bottleneck, because it does heavy use of the CPU as far as I know. One reason is, that they use the CPU based Havok physics engine and furthermore they do much stuff on the CPU that is today done on the GPU.
As Windows always uses a pagefile, no matter how big your RAM is, you can speed up all programs by moving it to the SSD (or better use it as your system disk and install Windows there).
Windows creates a pagefile only as long as you havent disabled it, which can of course be done, even if its not recommend (because some software rely on it).
But even if it creates it, this doesnt mean that the file is really used that much that it would decrease the performance when enough RAM is available so that the difference should be marginal, no matter where you put it.
Still you are right, that the file should be located on the SSD if you want to get the best performance, but you also have to consider that the file gets written very often and this can decrease the lifetime of a SSD!