The Achilles LT-2 is perhaps the lightest inflatable dinghy on the market at 29 pounds for the rubber bits, plus 8 pounds for the wood
floor and 12 pounds for the seat, oars, and motor
bracket. So 49 pounds all together. Plus motor
. It doesn't plane; you would want a 2-3 hp motor to go with it. They are functional but slow and of limited capacity. Nonetheless, the LT-2 would be my first choice for a "standby" dinghy carried deflated below decks, either as a spare or on voyages where it is anticipated that dockage is available and a dinghy will be rarely used. The Great Loop and a number of other inland journeys are often undertaken with no dinghy at all.
The air floor dinghy you have now is probably the best you can do size wise if you want speed. As you're discovering, the paradox of inflatable dinghies is that they are rarely deflated because it's time consuming and physically demanding.
There are an increasing number of good inflatable kayaks out there, many under 30 pounds, but they will not take a motor and you will get wet making them marginal for dinghy service
. See for example https://www.rei.com/c/inflatable-kay...%3A20+to+29.99