Cat6 and Cat6a comes in UTP. You do not want to get into STP. Forget about the terminating it, you need to have it properly grounded as well. So the termination aspect is not horrible, but now you have that extra step to ground it. If there was a lot of interference, then you need to start looking at STP.
If it is a sealed conduit, direct burial may not be necessary. I have non-direct burial in a sealed conduit. One end of the conduit goes into a utility box on the side of the house, goes underground and comes up in a box that is about 18 inches off the ground. The schedule 40 box has a faceplate that has a seal on it.
This is what I would do. Get Cat6a cable. If you want burial cable, then go for it. Terminate the cables on each end with either Mini-Com or Net-Key jacks and use faceplates. Then you just run patch cords from there.
Switch wise, if Fast Ethernet is acceptable, you can find some pretty cheap used switches. You can find an 8-port Fast Ethernet switch on eBay that is manufactured by Cisco and it has one Gigabit Ethernet link on it. So you can feed the switch via Gigabit and then have 8 Fast Ethernet PoE ports. The ports are only PoE (not PoE+ or PoE++) but 15.4 watts per port should be plenty. The switch can provide 15.4 watts on all 8 ports. You also now have non-blocking capability since all 8 ports combined will be only 800Mbps and you have a 1000Mpbs uplink. You can find this switch on eBay for around $40. I can assist if you need assistance in configuring it.
● Operating temperature: 32 to 113ºF (0 to 45ºC)
● Storage temperature: -13 to 158ºF (-25 to 70ºC)
● Operating relative humidity: 10 to 85% (noncondensing)
● Operating altitude: Up to 10,000 ft (3049m)
● Storage altitude: Up to 15,000 ft (4573m)
For wireless, just use a separate box. You can find some pretty cheap AP's that are PoE powered as well. You would be limited to 802.11n speeds with 100Mbps though. If you want faster, then just run a second Cat6a cable in the conduit.
If you're buying a spool of cable though, if the distance it 70 feet, then you could just run 4 or 6 (6 is the limit to a single gang faceplate) and then you never need to worry about future growth or trying to get another cable through the conduit. Cat6a is also good for 10Gbps at 100 meters. So it kinda future proofs your setup.