this is a pain for me. since launch my character has played a .... sort of good guy and it was quite easy to do and I was able to get most of the bits and bobs I need. I have never done a piracy mission or a massacre mission but always do the "kill bad guy" ones. yes I know elite has a very large grey area on good and bad guys but still......
but with the on foot stuff, maybe it is just me but it seems really hard to get anywhere without your character being a crazy mass killer. I feel - again perhaps because I don't know the mechanics as well as the ship part - that the game is forcing me to break character if I want the "good stuff"
As long as you aren't seen doing it, stealing stuff is easy - although a suite with Sprint Duration might be useful at times. Even going around and shutting down the alarm (and access level scanner) can assist in murder-free larceny... If you get seen, run away, wait a minute or two and the fuss dies down, then do a bit more. If the alarms are shut down, even data downloads can be done successfully, although they still flash lights locally if you are downloading stuff that is marked with the alarm symbol.
An excellent source of 'good' goodies can be found on the Larceny missions - suit schematics aplenty, remember your ebreaches to open locked boxes.
Abandoned settlements are great, as are the power restore missions, although both can spawn scavengers, occasionally in large numbers. As long as you have a good supply of ebreaches and a power regulator, all of these can be brought back online and pillaged, and if you get scavs, additional bounties for rep & credits.
Investigate all of the Irregular Marker sites you can spare the time for, grab missions sending to to 'recover' from a shut-down settlement, all of these will permit a Lawful approach.
I just chose a life of crime a few years ago, it works for me!