Samurai is somewhat unique in it has thresholds more than a definitive "BiS." Basically, you want to find a Skillspeed tier your comfortable with. I'll list the most common ones...

http://ffxiv.ariyala.com/13I6A - 1787 - 2.05
http://ffxiv.ariyala.com/132I2 - 1551 - 2.08
http://ffxiv.ariyala.com/1310S - 1195 - 2.13
http://ffxiv.ariyala.com/1309C - 966 - 2.16
http://ffxiv.ariyala.com/13304 - 521 - 2.22

1551 SkS and 1195 SkS are generally popular, though the 521 Crit built also works well but is more reliant on having a Crit heavy comp (SCH/DRG/BRD). What I suggest is using this threshold list by tossing on some random gear with SkS and seeing what you like then working towards the build closet to it.