What are the "hot" prefixes? For artifice, making crystals, hilts, and enhancements, that would be "Advanced". Most of what you can craft follows the Linear RE path, not the Prefix path.
As for shields, foci, and generators, I don't know how the other skill 400 artificers feel out there but my response is learn what classes need, check what stats are on the schematics, then look at a chart or table of what prefixes exist and figure it out. Here's one very simple one
. Or check out Ask Mr. Robot's Item Database
. Mr. Robot will show you the stat increases for different prefix variations, but I find it's incomplete at times, leaving out things like Force Power or Tech Power.
The reason why is that SWTOR is notoriously erratic in what stats it puts on gear as levels increase. For instance, aside from Aim, Endurance and Tech Power:
- at level 33, a Premium generator has Power for a stat
- at level 36, a Premium generator has Accuracy and Power for stats
- at level 39, a Premium generator has Surge and Power for stats
- at level 43, a Premium generator has Accuracy and Critical for stats
That inconsistency is nothing compared to what you'll find with Enhancements. High level Enhancements will often have 3 variations on a build. You may find a set with Endurance, Critical and Alacrity with three versions: one with high End and Crit but low Alac, one with high End and Alac but low Crit, and one with high Alac and Crit but low End. As a result, there are a ridiculous number of high-level Enhancement schematics that seem to have been added purely by passing the stats through something that calculated every possible permutation of stats, whether they make sense or not. You want an Enhancement with Endurance, Absorb and Alacrity? It's in there! I have no idea why any shield using class would want Alacrity, but you can make them all the same.
So, again, the best advice I can give is to know your potential customers and figure out what they'd want. It will narrow down the number of schematics you need to buy (if you haven't already bought them all from your trainer) plus it will get you thinking about what skills different classes have and how they play -- and if you PvP, knowing the other classes' strengths and weaknesses will make you a better PvPer. Too many people don't know how to play their own class; it's rare to find someone who knows how their own class can beat each other class.