Those are very nice. I'm particularly fond of the greyish-brown thatch, which looks very realistic to my eye (although it can vary in colour -- I've seen thatch that looks just like that and I've also seen it much darker; I presume it varies depending on the material and the length of exposure). I also love the little plants around the base of the walls; these small details really bring them to life.
And yes, rectangular thatched halls will do you for pretty much any period up until the introduction of chimneys in the, er, middle of the middle ages.