Often I plot a lot of lines and the legend obscures some of the curves, especially if I do not want to re-scale the axes to make room for the legend.
Taking my cue from what colorbar() does, I re-scale the figure and place the legend to the right of the plot. I have to dink around to make the
legend fit in this space but it works OK. This is also handy for contour plots that have the contours color mapped.
In the vertical I usually put the legend even with the top of the plot.
My suggestion is that the options for legend location include an option 'outside right' to automate this process.