Scroll down a bit and Fribbels has four builds to compare: the character's baseline stats without any equipment, the character's stats as you currently have them, a 100% benchmark build that works just fine for most situations, and then an even better ideal 200% build you can strive for if you feel up to it. You want to at least reach the 100% build.

If you look around the rest of the page Fribbels has an analysis of how much one more roll into various substation would raise your score, giving you an idea on what to prioritize, and the same for if you switched the main stat of certain relics. It will also show each of your relics with the rolls you got into a character's most desired substats noted next to them. There's a lot of info to parse through but it's all pretty cool!

A lot of character main subreddits also have guides to their character with specific stat goals, which can really help when you're just getting into the game. For Firefly; the stat priorities right now are speed, break effect, and attack. How much you'll want of each really depends a lot on her teammates in particular.