Thanks for the thoughtfull response 
I tend to get blisters on sk8 hi/lo where side panels are stitched to the toe panel.
I just really like the contours of the contrast stitching on halfcabs. lovely aesthetic.
maybe they'll make a half cab decon someday, that would be rad
i opened up an old pair of halfcabs, removed the foam ankle inserts then sewed them back up. unfortunately they were just too floppy but it was worth a shot
currently skating a couple pairs of HUF classic hi so i can pretend i'm in SF :p
Yeah I get what you mean about the stitching in the wrong place on Sk8 versions.
For a long time I could never fit size 11 well, but when I finally gave up and went to size 12 they just fit so much better. Not that it would be an option for you or others, but where the stitching is on the inside just over the pinky toe can be a deal breaker or a perfect fit give or take a couple of mm in terms of the length of the shoe.
I had also deconstructed an old pair of Half Cabs a while back just to see, which didn't work out well at all, I guess much like your own experience. The padding could be replaced with a thinner / not so dense strip of foam, more so than the thick rigid ankle cuff that they put in them, but that is a lot of work for a shoe that could only last a month or so if skating regularly.
Seem to recall someone else drilling holes through it from the inside to soften it right up, but that seems like a very weird way to go about it too.
The Rowan 1 was the closest shoe to a Half Cab as well, but if they are phasing them out, I don't know how good that would be to try to find some, only to have no more when you want them.
They were pretty comfortable for me anyway, if not a little big, compared to the fit of Half Cabs, but you could add them to your list of shoes to try on.