What happened to ditching the fan on the SP4? Microsoft very briefly glazed over the "hybrid" cooling system. If the SP4 didn't have a annoying fan i'd be more apt to upgrade.
There are plenty of options....
http://www.amazon.com/s/ref=nb_sb_noss_1?url=search-alias%3Dcomputers&field-keywords=usb+3.0+dock&rh=n%3A541966%2Ck%3Ausb+3.0+dock
I bought this for my SP2, it has gig Ethernet which Microsoft didn't at the time. I also don't have to upgrade or change my dock every time my device changes. it's also cheaper http://www.ianker.com/product/68ANDOCKS-BA
This same thing happened to me. My monitors would get a signal, but would be completely black. I uninstalled and reinstalled displaylink. I also downloaded drivers for my monitors, they were just listed as a generic monitor under device manager.
I perordered the SP3 and touch keyboard. I was charge $1 for each on my CC, MS will charge the full amount when shipped. This is how I purchased my Xbox One as well.