to add my labels, although I don’t really like where they end up:
With the GR backend the annotations that are set to the last subplot are over all other elements, and thus we can put these labels A, B, C,… as annotations in the last plot, but wherever in canvas one wants. With PGFPlotsX they only appear within the plot region of the corresponding subplot.
I will keep searching for a better solution (other than opening the file in inkscape and moving the labels by hand). I want to stick with PGFPlotsX for the consistency of the fonts, of course.
I had the same problem as you Imiq with the same desire to use pgfplotsx as a backend of plots. I didn’t want to change to GR because of the nice latex integration and tikz export ability of pgfplotsx. I ended up going with this slightly nasty solution of editing the output file to shift the title:
savefig(all,"Sensing.tikz")
test=readlines("Sensing.tikz")
outfile = "Sensing.tikz"
open(outfile, "w") do f
for i in 1:length(test)
test[i]=replace(test[i], raw"title style={at={{(0,1)}}" => raw"title style={at={{(-0.2,1)}}")
println(f,test[i])
end
end