I'm kinda with the crowd on this one, Question.
In my opinion, picking on the Belt was not the right thing to do.  However, combining a "bizarro race" (i.e. a race who couldn't walk in a normal D&D town without causing people to run away screaming) with region-specific feats from another campaign setting and a prestige class that may not be any better known to your DM than me, you have a character the DM considers unmanageable.
You have what the old "Magic the Gathering" deck-builders called a "Combo Winter" deck.  None of the selections you made are in themselves bad, but the combination of them makes an unbalanced character build (you'll win a lot, but won't allow others to have fun).  In my opinion, the Eberron feats/items and the prestige class seems to be at fault more than anything else.  As a DM, I would have intercepted you earlier in the process and made you remove them.
Lose the Belt and be glad he doesn't ask for what he should be asking for.  He's being more than reasonable.