I tried smuggling, only to find that it's just as boring, just with a different group of people to avoid on your routes. I know some people enjoy the thrill of encountering resistance (whether a pirate or lawful), so they can RP, fight, flee, etc. But I really don't, I just want to make my credits and get it over with. I find sitting around a populated system (such as NY) with my freelancer and chatting with people and seeing if any jobs drop into my lap to be far more enjoyable than trading.
My current trader is my original Discovery character, Bretonian ex-pat turned Zoner, Isaac Drake. He has RP to back him up. He chats with people in the systems he passes through. He chats with pirates, and pays without much fuss, and even makes agreements ahead of time if he know he'll be passing through a pirated system. He flies a Whale... I could say because it's the perfect large in-RP transport for a peaceful Zoner, but mostly because it's the largest transport which can reasonably still be considered 'smallish', at least when compared to the Adv. Train, Lux Liner, and Tanker. Plus I think it looks cooler than most other transports.
I don't really enjoy playing Drake, at least not as a trader. I only play him when I need money, and my goal is to make as much as possible as quickly as possible without doing flagrantly ooRP things (such as using Chokogu as a highway). I rarely trade more than a half-hour or forty minutes at a time, because I grow bored quickly. Grouping with other traders to chat with while you fly is nice, but, to be perfectly honest, I'd just as well use the private comms for pure OOC banter as I fly along. The only reason Isaac Drake still exists (at least in his current profession) is because trading is a necessity for anyone without ungodly amounts of free time or some salable talent (such as signature-making).
My first character upon re-joining the in-game community was Garrett Frost, a Junker trader and sometimes smuggler (though never a slaver). The Firefly is a nice enough ship (though ugly texture), but it didn't make money fast enough, so I ended up resurrecting Drake and getting him the Whale (after a Zoner Guard tag... ugh). Not sure what I'll do with Garrett now, since I do like him as a character, just not as a trader. I think I may get him a nice freighter when things get re-balanced in 4.85.
Drake will be switching to Jinx's wonderful Zoner Transport when 4.85 rolls around. Fitting for the character, as well as having more cargo space so I'll make money faster. Best of both worlds, eh?
I'm not looking for tips on how to make trading more enjoyable... I know them all. It just... Isn't.