Any time you want to shop for tents on a weight basis, be sure to weigh the actual tents in question. Maybe this has changed in recent years, but when I worked in the biz, real weights and listed weights were not even close. This goes on with frames also, there are some numbers that are not correct on charts, the companies just fake them because they know what we want to hear. You may think you are only dialing on a 2 pound difference, which is a 40% increase, but there has to be more to it. You are either going to a less rugged tent say a lighter pole config (which probably doesn't mater). To increase the floor space laterally by 100% or even 75%, you should experience a direct increase of weight of the same extent and that assumes no increase in the tent height.