Other than the SWR and R = and X = numbers, nothing else you can tell in the shack without replacing the antenna with a good RF short circuit. That would allow you to measure cable loss; but you can't measure that with the antenna connected. If you can't hear ANY beacons I'd be surprised. Of course, this varies a lot by location but you seem to have for of them fairly close. I can routinely hear about six 6m beacons here, 24/7 -- they're close enough that propagation doesn't effect them (within about 350 miles). Then, a whole lot more than that when the band opens in almost any direction.