Rom is smart... he's just dense and naive as all heck. Nog not wanting to end up like him made perfect sense. But despite it all Quark does care for his brother. This shines through often enough and Rom gets a few snippets to rise to greatness in the next three seasons. I still scratch my head at how his character arc ended but... I guess that was the point. You'll see.
As for Garak. Well, he's in more episodes than Jake for sure. In seasons 5-7, he's literally in the majority of the episodes too minus the filler ones really.