Read this thread:
BTW I make most of my money with an Armstech alt > purple barrels for "all" levels & lvl 49 purple augments. Because all people "hate" Armstech, the crafting missions for researched materials (investigation) are so darn cheap that your profit margin for the barrels is quite good and the overkill & fortitude augments are very much sought after.
You should at least have one Armtech alt as you will have "fresh" barrels all the time while leveling.
As for slicing: it's a good skill to make "fast" money but you will need scavenging for crafting either barrels (investigation) or augments (slicing), so if you don't have another alt to gather scavenged materials you should take scavenging at least while leveling (dropping it for slicing later on is no prob as getting slicing to 400 by sending your alts on missions takes about one afternoon and crit-ing you'll get lots of crafting missions & some schematics that way).