Speaking of Cloaks, why did the Defiant have a Romulan cloaking device, rather than Klingon?
The Romulans were the original inventors of the cloaking device. Besides they have greater finese and skill that your typical Klingon brute (and we got to see Martha Hackett in another too-short Trek role).
The one thing that bothered me with Romulan ships was that we only ever saw the D'deridex-Class. We saw several Starfleet, three Klingon, three Cardassian, and three Dominion classes engaged in fighting, but only one Romulan (which never seemed to fair well in the battles either).