I guess I could do only one SATA express port and get a cheaper motherboard. I really only will be using the SATA express for the SSD right? So one of those and two PCI x16 would be okay?
SATA Express is only for the SSD, yeah. PCI Express can be used for plug ins that require a lot of bandwidth (e.g. graphics card, certain SSDs).
I think this is a good one. It has two SATA Express and 3x PCI Express.
EDIT: As for memory, if you're cheap, you can get away with 8 GB. It's usually enough unless you run virtual machines or do software development. Regardless, you should probably pick a Kingston memory as they tend to have lifetime warranty.
Ok thanks for the MB recommendation that helped a lot. Price isn't a HUGE point but I'd of course like to keep it as reasonable as possible. Kingston memory was slightly cheaper anyway so I changed it. It does have 10 instead of 9 latency though. Probably won't make a difference.