Loadout Overview
s1.1 vs s1.2
Picking between fireballs is almost entirely preference, there is no agreed upon better move. Both moves work fine with whatever loadout you want to play.
s1.1 is the most traditional fireball there is, you control the speed by holding 4/5/6 and the cooldown is reset on hit, creating something resembling the one fireball rule from other games.
s1.2 is a bit unorthodox, the fireball is shot towards the ground, so no full screen zoning. The is also no air version of s1.2. Instead what you get is a better frame data fireball that rewards you with a knockdown or juggle on hit.
Picking what fireball you want to play with is a matter of preference and matchup comfort.
112:
This is the classic shoto loadout for Chel. s3.2 allows Chel to confirm her jabs into damage and positioning. Its not a high damage loadout, but every hit puts you back at full screen to zone. Very simple loadout to play, if you've played any other fighting game you know how to play this version of Chel.
X13:
Most players who play Chel eventually come around to playing this loadout. Despite 112 being very well rounded, it simple doesn't do enough damage. s3.3 sacrifices any and all utlility in this move slot for damage. This helps unskew the risk of going for throws, as you can spend a bar for meaningful reward with this loadout. The fireball you use is entirely up to preference.
What about...
s2.2 is a less rewarding, but faster reversal. Its not really any better at anti-airing than s2.1, occasionally its worse due to a shorter hitbox. And you sacrifice almost all damage you would usually get for a successful reversal/anti-air from s2.1. The only saving grace for s2.2 is that it is harder to option select, but thats really not a good enough reason to pick it. If you are brand new and want to pick a loadout though, it is easier than s2.1 to use.
s3.1 this move might be the worst move in the game, in theory it should be a middle ground between damage and utility. Unfortunatley it doesn't offer either. It doesn't hit crouching opponents at all. It doesn't combo from jabs. It doesn't do any damage or give you good combos. There is no reason at all to pick this move.