"Bassy Looking" is combination of cover and structure. Cover is not limited to just weeds, and structure isn't just off shore. Cover referes to anything in or directly over the waterline, besides the bottom or the water. Structure is simply the bottom - you would use terms to describe that structure, such as point, ledge, depression, flat, creek channel, etc..
You are looking for spots where several elements intersect. For instance, a cove off a main point with a strong secondary point that has creek channel, a shallow weed flat, docks, and some deeper water nearby would be a really "bassy looking" spot. All those terms describe both structure and cover.