You tell us “I am using carbon rims and carbon brake tracks...”
Then you share that you weigh just under
#300 , and you are disappointed about your rim brake performance in the fog where you live.
But you are quite proud of the fact that you’ve got your bike weight at about
#16 .
You checked with a reputable titanium frame shop (Ti Cycles perhaps?) who quoted you a realistic price to modify a Litespeed Vortex to accept disc calipers including re-setting the rear triangle?
Come on! If your titanium frame is appropriately overbuilt to not flex in the bottom bracket under your body weight then you’ve got a keeper. Lack of flex is a necessity for you - good!
Next up, the braking. It is bad by your report. Did you have conventional aluminum clincher rims on there before with proper machined sidewalls? What was your thought process when you went with the carbon rims? There are plenty of aluminum wheelsets that are as light or lighter than carbon, if weight reduction was your objective.
When asked for specifics about your wheels, brakes, etc... you trickle out little bits of data at a time in a way that has the participants in this thread thoroughly mystified. Dang!