I’ve looked at the numbers before and unfortunately it doesn’t really make sense.
Having an Ultralight packraft with a wraparound floor wouldn’t make it stronger because the ultralight floor fabric is the same strength as the ultralight tube fabric.
Compared to a standard weight Telkwa, substituting ultralight tube fabric in a Telkwa only reduces its weight by about 400 grams (less than a pound) but it makes it much weaker (too weak for whitewater paddling) and it’s still heavier than a Skeena (which is whitewater capable).
I thought about developing a floor fabric that’s somewhere in between the ultralight and standard weights, and I can’t recall the numbers at the moment, but the weight savings were only marginal compared to the standard weight floor fabric – not enough to justify the significantly reduced strength.