FYI, the weight of the DSS Single Tank Rig w/ Medium Hybrid Kydex plate, Hogarthian Harness, LCD 20 Single Tank Wing w/ 30 mil Bladder as per Tobin is ~6.6 lbs, but that also includes more webbing than you are likely to use.
They furnish enough webbing for very large people. You could also save a bit more by leaving off the “butt” d-ring and keeper, they are a bit under 1/10 th lbs. He doesn't recommend or sell pockets.
I weighed my Express Tech using a digital luggage scale. I hung it from the shoulder straps. The scale was accurate and in line with the scales at the airport. 6.5 lbs. Though I'll double check it and the webbing width tonight.
As far as our luggage weight, my wife and I travel with our snorkel gear (full size fins, masks, snorkels, mask boxes (so they don't get crushed in transit), Xrite mask bags (protects the masks in the wet bag on the boat), Wrist mounted computers, Aqualung yellow mesh wet duffel bag, two 3mil full suits, boots for each of us and my BCD - she rents her jacket BC at the destination. We rent the regs, tanks, weights and weight belts at the destination.
Our luggage for our last trip (15 days on STX in a villa) consisted of two full size suitcases containing a few days worth of clothes, dressy shoes, flip-flops, my BC, several pounds of household supplies (we were staying at a villa and is typically cheaper to bring staple goods with you than buy on island, like pasta, salt/pepper, etc.). We have one wheeled carry-on with our breakables, masks, 1 set of clothes each. Then we each have two personal bags containing travel blankets (it gets cold on them planes), travel pillows, a netbook PC, wallets, iPhone, phone and PC chargers...
In all the checked luggage weighed in at 47lbs and 48lbs on the way back once depleted of consumables, but added in some souvenirs. My wife heavily questioned my need to bring my BCD due to the amount of weight it takes up. Our suitcases are probably 10-15 years old - at least, so we're also considering whether or not looking into modern luggage that would hopefully cut the weight but not get destroyed.
My defense for bringing my BC was that since I was doing my AOW, I wanted to be comfortable and I don't like jacket BCs. I don't particularly like being crushed when inflated or the feeling of being restricted. I've made due with jacket BCs in the past, but I didn't enjoy them. I'm paying a crap ton of money to dive, I'd prefer to be as comfortable as possible.