I know it's round...but what about a Weber 26" Kettle? Big enough to move your food around, plays well on a deck......How much grilling are you looking for vs. smoking? If it's a straight smoker would look into a used cabinet style smoke like the BW suggested...
Red Weber Master Touch- "Old Betsy"
"Yeah, all those things, responsibility, pressure. It`s a bit stressful. I try and come to terms with it by not thinking about it." - Joe Strummer