Having that nozzle down in there can really throw off what u think you have in there.
Is the carb stock ?
I deleted all the rest of the questions i had until you answer that one up there with more accurate MPG figures.
Fill it up to a known level you can remember and fill it up that much next time. Like an inch from bottom of the filler.
No that's not normal for your weight.
I am going by another rider i know that weighs a tad over you.
he gets +60 mpg highway on a travel loaded bike.
If you had leak, you would know it.