We're most of the way through this adventure and I have to say the loot has been pretty slim for 18th level characters. Compared to Dragotha's hoard in the next adventure this is a paltry offering indeed. Then again his CR is equal to Brazzemal's +4. Am I missing something?
I believe that is because it is supposed to balence out.
You may be ignoring the large weapons.
The Players should be able to sell them at Mageport.
Well, Brazzemal's Aerie is in the 'next adventure', above the Wormcrawl Fissure. It is deliberately left undetailed (One would assume) so that a DM may place a wounded and/or beaten Brazzemal from KotR there, or do something else. IMC, I statted out his mate and had her guarding an appropriate-sized hoard. When the PCs took too long looting it after dispatching her, I had Dragotha send in a Wormdrake and a summoned Balor ally (My party had six powerful PCs), but the heroes prevailed.
As for the giants, I detailed the Palace of the Riftlord Achaime based on the border fort from the Istivin campaign arc earlier in Dungeon, appropriately re-sized. For the treasure there I took the combined loot of the 'boss hoards' from the old TSR G1-3 series, and set a 'Praetorian Guard' of elite cloud giants (based on 'The Storm Lord's Keep'Roc-riders), fire giant fighters and hill giant hangers-on of the King as inhabitants. The party decided to proceed on to the Fissure rather than mop up the city after slaying Brazzemal though, so my effort was for naught. (Although they might return there after the campaign is over...)
Anybody who is interested in time-savingly detail out Brazzemal's Aerie - seek out the Draconomicon web enhancement, it sports a CR20 red, a nice volcanic lair, and some minor minions. Add some younglings, and you are done :)