Back when I was a wee lad, the first original STAR WARS figures were the coolest things in Life. In some ways, they still are. The first LUKE figure and then BESPIN LUKE figure both sported YELLOW lightsabers. Some blah blah blah with Kenner and miscommunication with Lucas or something. Anyway, when the PREQUELS came out, we as fans had to swallow Mace Windu's PURPLE lightsaber (really, Lucas? really?). So my point of this post is, if Lucas had no problems with veering off course and having a PURLPLE lightsaber, why no YELLOW LIGHTSABER LUV for the fans? I would have been happy if YODA's lightsaber was yellow... although I don't think Yoda should have HAD a lightsaber, but that's another ranting post all-together. Hell man, how about that one scene with the Younglings... give THEM yellow sabers... it would have then tied in nicely, in a "Lucas Connects All" sort of way: Luke's figure had a Yellow lightsaber because in ANH and Empire, he was not yet a Jedi.... he was in early training. See, was that so hard?
Anyway, Yellow Lightsabers.
Overall, I think Lucas should have kept it to BLUE, GREEN and RED.
No taste the rainbow.
On a side rant... In the Prequels, I hated how all the Jedi had BLUE and GREEN lightsabers like it was the luck of the draw... I wanted the standard saber to be BLUE... with the Jedi MASTERS having GREEN; ie those who were powerful enough in the Force could forge a GREEN saber. That way when Luke show's up in RETURN OF THE JEDI.... sweeeeeet.