This board weighed 15.5oz. I removed all 10 of the blue capacitors and it now weighs 12.5oz. What is the initial grading and did I change that?

I always have a hard time grading boards like this. As it is in the picture I would say Peripheral low grade and I would hope that removing the caps would upgrade it to Peripheral High Grade. It seems to be on the low side of high grade, so I'm not 100% sure.

Yes, I'm still basically new at this so I'm not sure either. Aside from the gold pins and a few ICs, there are "tantalums" (any real value there?); but there are two rows of what look like MOSFETs and that's a fair amount of copper weight I would imagine.
Using the premise that the value of any PCB is directly related to the ratio of gold weight to overall weight, I'd like to see a listing of all of the types of items on a circuit board and for each, the weight and what percentage of that weight is gold. In that way we should be able to add up what is on a board to reach a more recognizable, consistent value. And it would be easier to know what, if removed, would add - or decrease - value.
Perhaps I am oversimplifying..

From what I have learned, (via this discussion board) the Telecom style boards have more layers and therefore more gold/copper traces. Tantalum Yellow and Black SMD do sell here for $9.00/lb, but I don't remove them from anything better that low grade boards.

I think the problem is that you can't always classify a board by the type of equipment it was used in. Your $25 network switch board is a big difference than your high end Cisco switch board, so just having a network switch board category won't work. Hard drive boards were all one category until the SATA - IDE hard drive board classes split up. Some of the early SATA boards looked just as populated as older IDE boards, but the connector type is an easy way to separate the class. Just when you get it figured out, something will change.
I'm sure the refiners have a very good estimation on what contains what and they control the categories that get passed on from companies like Boardsort.