Mac mini 2012 performance with LR4, PS6 and AE 6

The SSD will only be for the applications. I highly doubt that ill put any sort of documents or work with files from there directly. Which leads me to my second questions. What about using the HDD as a scratch disc (Digital drawing in PS and video work in Premiere pro and AE)? Would it be smarter to replace that with an SSD as well?

Reason I asked this is because I've never worked with a WQHD monitor. I've worked with a multi-monitor set up before its convenient for video usage and every day use, but I also hear that color calibration could be an issue due to the mini having two separate outputs.

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"In the Internet age, the bathroom is now the photography studio.In the film age, the bathroom was the developing lab.
And before the film age, I guess it was just the outhouse." - Anonymous