My biggest issue with the 2 DVI, 1 HDMI, and 1 DisplayPort is, yeah I can drive all three of my 1080p monitors with one DisplayPort daisy chain, but the monitors are all 1080p@144Hz. Then, they aren't specced to support 1440p or 2160p, but they actually can be forced to through drivers... If I want to do that I'm really starting to choke DP's bandwidth. Even having just two DP would allow me to daisy chain my two side monitors on one and drive my primary/center monitor with a dedicated DP.
Newer HDMI (1.3b?) supports 1080p@144Hz, but that would require me to get a newer monitor that supports that standard, I'm pretty sure.
I'm tempted to gun for the MSI 1070 mini instead of the Galax, but I'm afraid of the hacking I'll have to do to fit it in the S4 Mini.