I have used TCLAP for a month or so now. I think it would be great if I could divide the arguments into groups, so each group would be shown separately in the --help.
And maybe one could also specify a prefix for a group, so all arguments from it would use the prefix. So if an argument is in a group with prefix "s", has a flag "f" and a name "file", it would match a "-sf" and a "--sfile" in the command line. This would be very helpful if you have way too many arguments, but still want to be able to use the flags instead of the full names.