There are a couple of issues:
--There's no Martial Initiator prc that advances maneuvers as well as Skirmish/Sneak attack, so in order to get past the maximum of 4d6 that taking 5 levels of Scout and the Improved Skirmish Feat, you have to take EVEN MORE Scout, which further hurts your Maneuvers known/readied, Initiator Level, etc.
--Your BAB (which you will use for a few Maneuvers at least) will be severely hampered by taking levels in two different 3/4 BAB classes (unless you use fractional accounting)
Considering that Red Hand of Doom is designed for something like levels 5-12, if you DO try to maximize your Skirmish dice, you're only ending up with a handful of Swordsage levels.
My suggestion would be to ask your DM if you can use the Sublime Way Variant Ranger (below), and go with a melee Swift Hunter build (something like Scout 3, Sublime Way Ranger 6+).
http://community.wizards.com/go/thread/view/75882/19519074I hope that helps, there are probably other ideas, but this is what struck me first.
VB