Hi Bjorn,
I think the simplest way to incorporate PriceBTCUSD to the main graph is as following.
for your reference.
I considered doing that, but decided to add separate pages instead. I think it gets a bit messy if I combine too many options in one graph and on one page. I even made this monstrosity...

Also, the more data I add to a chart, the longer it takes to load, I think people using slower connections or need to connect from China, like dahongfei, wouldn't be able to load all the charts anymore. So new pages was what I decided on.
The "Swaps + Price Charts" menu entries now show three charts to analyse Price and Swap statistics:
- Price + lowest swap offer / highest swap demand
- Price + Sum Active BTC / USD Swaps
- Price + Average rate on Active BTC / USD Swaps (=ffr)
Hope you all find good use for the new pages.