I find: http://www.swtorcrewskills.com/swtor...rafting-chart/
For force users synthweaving will allow you to make armor, artifice will allow you to make lightsabers (among other things). These two crafting skills are fed by archeology, underworld trading, and (for artifice only) treasure hunting. Slicing is useful because you can get schematics for augments for synthweaving.
Cybertech is also a good choice because you can make ear slot items, and armorings and mods for custom (orange) quality gear. The grenades are also a nice bonus (Area of Effect damage and stunning on a moderate cooldown) Cybertech is fed by scavenging and underworld trading. And again slicing is good for schematics.
Biochem allows you to make consumable medpacs and stims (good for all characters). The character with Biochem can make reusable medpacs and stims. Biochem also makes implant slot items. Biochem is fed by Bioanalysis and underworld trading.
But it looks like you are playing F2P. This means you only get one crew skill unless you pay to unlock crew skill slots. With this in mind, if you are not going to unlock additional crew skill slots you might want to reconsider your position of not wanting to do just gathering. The fact of the matter is that you could do synthweaving on one character and archeology on the other, but that would only get you premium (green) quality crafted gear which is easily out done by quest rewards. You would need to acquire materials from underworld trading to make gear good enough to use and sell.