He was not a good guy, as a smuggler.
Real smugglers are ( OF COURSE ) not a group who all have the same opinions of themselves. Of course some of them think well of themselves, and others don’t. Also not all laws or regimes are just, so I might agree that certain of them are doing good by smuggling some things.
A bad message to youth? No. The bad message to youth is making a good movie, and then stupidly changing your mind and changing the films in a dirt-stupid way where Han didn’t shoot Greedo before Greedo had a chance to kill him, because there’s no way Greedo would miss in that situation, and Han knew that, so of course he shot first, or else he would be dead, and never would have become “a good guy” in any sense.
Han was smuggling “spices”, thought (but AFAIK nowhere accurately revealed) to be an illegal addictive substance.