You want to dress well? First, stop making your clothing selections based on what you think makes you look big. That is a surefire way to make you look like an idiot, like you have no sense of style, or both.
Once you start choosing clothing based on what actually makes you look good (according to normal societal standards) and not what makes you look big, you will immediately improve your appearance by 10-fold and open up a whole new world on options.
Furthermore, when non-bodybuilders say things like "you look like you lost weight"...or "you look slimmer", what they are most often saying is that you don't look as fat as you did before. They are not saying you look less muscular.
You are what you are. If you think you look too small when wearing properly fitted clothing (according to society), then get bigger, but I can tell you with 100% certainty that even a guy with your stats, who dresses well, is going to be exactly what most women are looking for. So, rather than trying to look "big" try to look "good". For the most part this means tapered waists and proper fitting shoulders, along with a shirt length that doesn't go down to your knees (eliminate all shirts that make you look like you're wearing a tent) and form-fitting, but not tight pants.
Since most clothing manufacturers cater to those with little muscle mass and large midsections, this clothing is harder to find, but when you have a great physique, anything you wear--as long as it is properly fitted--is going to look good on you. It's like women who are lean with great proportions--just about anything they wear looks good on them, while fat women are constantly complaining that nothing looks good on them. They are always trying to hide their true selves by wearing "deceptive" clothing. As a bodybuilder you will never need to go this route. Your challenge is just the opposite--finding clothing that reveals your true self. This will only be accomplished with properly fitted clothes...and there just isn't that much out there for bodybuilders, or even those with athletic builds.
This means you may have to pay more and/or purposely seek out those items/brands that fit you well, but above all, get away from the "must look bigger in clothing" mentality that so many bodybuilders have today. If you have a great physique, baggy clothing does NOT make you look better. It may make you look bigger (and fatter), but certainly not better. Bodybuilders who dress like that are doing exactly what fat women do--trying to hide their true selves with deceptive clothing because they think properly fitted clothes makes them look too small. As a result, they end up looking like shit. If you have a great physique, then reveal it with properly fitted clothing. Don't hide it with baggy nonsense that just makes you look like clueless moron.
You will also find that when you stop focusing on looking big and instead start focusing on what makes you look good, that you will garner more respect from non-bodybuilding men and women (which is just about everyone). When bodybuilders wear baggy or super tight clothing they either look like they have no sense of style or like they are showing off. The former will be perceived as a goofball and the later as an egotistical asshole. Rather than assuming those roles, try to fit in with everyone else by wearing normal, but properly fitted clothes and you will gain many compliments, while making others think you're MORE THAN just another bodybuilder obsessed with his body.