This is a work in progress as I find time so please be patient. If you have input for it, please post it as a reply and I can add to this, thanks!
First, lets go over what skills are classified as what.
Crafting
Biochem
Cybertech
Armormech
Armstech
Artifice
Synthweaving
Gathering
Scavenging
Archaeology
Bioanalysis
Slicing
Mission
Treasure Hunting
Underworld Trading
Diplomacy
Investigation
It's recommended that the first character you start, you should pick one crafting skill, one gathering, and one mission skill. To make this process easier, I'll be putting some entries down below to assist you in choosing what goes well together since you want to pick a combo of abilities that will supply you with what you need so you can craft your gear. As I mentioned earlier, this is an ongoing project so if it doesn't look complete, come back to this post later for any updated info!
Biochem
- Description: Skill used in crafting medical supplies, performance-enhancing chemical serums and biological implants. This skill makes consumable items as well as some items you can equip on your character to boost more stats.
- Recommended Gathering: Bioanalysis
- Recommended Mission: Diplomacy
Cybertech
- Description: Skill used to make droid armor, earpieces, grenades, armoring, mods and miscellaneous gadgets.
- Recommended Gathering: Scavenging, Slicing(for patterns only from what I've seen so far)
- Recommended Mission: Underworld Trading
Armormech
- Description: Used to build armor for non-force classes.
- Recommended Gathering: Scavenging
- Recommended Mission: Underworld Trading
Armstech
- Description: Builds weapons for all classes.
- Recommended Gathering: Scavenging
- Recommended Mission: Investigation
Artifice
- Description: Constructs lightsaber modifications, enhancements, generators and focii.
- Recommended Gathering: Archaeology
- Recommended Mission: Treasure Hunting
Synthweaving
- Description: Used to build armor for force users.
- Recommended Gathering: Archaeology
- Recommended Mission: Underworld Trading
Slicing
- Description: This isn't a crafting ability but I figured this needed an entry listed. Slicing allows you to lock pick boxes for credits. When you send your companion out on slicing missions, they may occasionally come back with items that give missions for particular crafting professions. You can also find cybertech patterns through this skill. I'm not sure about other crafting patterns since I haven't seen it do that yet.
Additional Linkage
I figured I'll list some other helpful links here to assist those that want to read more into these skills while I refine my info up top.
- Crafting Guide by Starwarsmmolevelingguide.com
- This guide has some nice picture representation as to what works together as well as what classes can benefit from what crafting professions. Not a bad site and it provides a ton of information. I figure my post above is just a generalization but if you want a lot of the nitty gritty, this is the link for you!