My reason for getting a 16gb set is to eliminate any future compatibility issues upgrading from 8gb to 16gb. Would be kind of a bummer to receive another 2x4gb set to stick in with my 8gb and find it does not work. It should work, and if it doesn't, through an RMA or two you should be able to find a compatible set, but I would rather not take that risk, and just went with a full 16gb set. With 16gb you would likely rebuild the rest of the PC before you had to upgrade your RAM.
I didn't look at the MOBO, unless it has specific features you want you can definitely shave some cash off there.
actually to MOBO you mention was on my list if has a good deal an alternate part. Some article i read made a compelling case at the time for the other with the included wireless. Cannot remember link know been reading to much last few day running together. Case was for future expansion. The SSD was for the cache drive for the I5 that is the biggest it can take its just holds mainly the OS from what I unterstand