In Liber O, Crowley says to draw the hexagrams of the other planets in order, one over the other. A slightly more streamlined version uses the unicursal hexagram; as this form of the symbol has two lines crossing through the center where the Sun is, the figure can be drawn in a less iffy manner. It's still not perfect, but it seems to work better (evidently so much better that Regardie decided to include it in The Complete Golden Dawn System of Magic).
Recently, however, I happened across a blog post that pointed me to the old Golden Dawn document "Polygons and Polygrams", where the unicursal hexagram is called the "irregular third form", or "pseudo-hexagram".

Since the Sun is right at the top of this hexagram, would it be possible to use this figure in place of the regular Solar hexagram in the GRH? Or would it create an energy imbalance of some kind?
Personally (and this is a completely uninitiated, but educated, guess) I think that this would be fine if the Solar hexagram was the only one being drawn (i.e. at all four cardinal points) for that instance of the ritual. After all, similar substitutions have been made throughout the Golden Dawn system over the years; the most notable I can think of is that Daath has no God-name, so for the Middle Pillar it 'borrows' one from another Sephira.
Any thoughts on this - or observations, if anyone is inclined to try this out - are welcome.