For the longest time I have been trying to figure out some use for Elite Honor Guards and Ghosts in large numbers.  This was how I stumbled upon a fairly sound victory.  I made roughly 25 Ghosts and 25 EHGs, both fully upgraded and with Shield of the Forerunner.  The result was a fairly impressive force. 

The player was quick to counter, making Banshees, Jackals, and Hunters, but by dividing my team I was able to cover each units weaknesses.  I found that ghosts are fairly adept at taking out Banshees, as Banshees anti vehicle projectile is slow and innately inaccurate.  Couple this with shielding and dodge ability and my Ghosts were able to defeat them.  The Hunters were an easy kill too, all that was required was scouting around for where they were being kept and then stealthing my elites in.  As the Arbiter came to save his army my Ghosts bashed en masse into him.

As base killing was slow for me, the Arbiter had the good strategy to build Locusts to take out my base faster than I could his, but a fully upgraded PoR was very skilled at destroying them.

So, experienced players, any advice on improving my strategy?  How should I change it for other leaders, such as the Brute who can conquer masses of weak units fairly easily, or UNSC armies?  I base my victory largely on having an army fully shielded, so I would like to keep every unit in my army a type that uses forcefields.  Would Wraiths be better?  I only didn't choose them because I couldn't spam 'Y' on the Arbiter.  I assumed he would simply jump out of the hot zones.  Or, in your experience, was my victory simply a fluke?