SWGOH Resource Flowchart 2.0

Breaking away from the path a bit here, I'm going to recommend against moving forward with character shards, so that you can focus solely on unlocking Darth Malak. Darth Malak requires 10 characters total (Jedi Knight Revan and any 4 characters used to unlock him, ditto Darth Revan). The catch is, each of the 10 characters needs to be at a power level of 17,500 in order to be eligible for the event. Getting him unlocked early in the game will help you quickly climb and dominate the Squad Arena, which will help generate increased crystal income.

After unlocking Darth Malak, you'll want to also bring his power level up high through gear ASAP. As such, I'm recommending that you focus solely on getting Darth Malak unlocked, then powered up to at least Gear Tier 11 before proceeding with LS/DS hard nodes.