Using levitation in your playstyle is a very good addition to have.
It's useful for the following.
-Invincibility: On wake-up and in certain moments, I've experienced my opponents attack(s) whiffing.
I wish I had an exact frame count, or a more specific idea in which these frames are active. But I haven't the frama data or the extensive knowledge of it, seeing as I can't practice against the cpu in a controlled eviornment.
-Building meter: You can cancel the levitation directly into a high/low block. Giving you a bit of meter. You can perform this by pressing d,d,d,u+BL
-Mind games: Knowing how to levitate cancel can help tremendously in certain situations, believe it or not.
While zoning with sindel you can add the levitate into the pattern you're using to zone your opponent. If you think your opponent might punish you, or you just want to confuse them even further. Levitate cancel into a special attack most likely being a fireball or hair whip. This can keep youre opponent guessing and very cautious.
-Baiting: You can casually levitate and punish attempts to attack you, with fireballs depening on the distance.
Sometimes you can levitate, dash, and punish opponents who teleport or whiff an attack.
More commonly though, you'll find yourself fighting characters with teleports or specials that can be punished easily. Some not so much like Kung Lao's hat.
--Levi-cancel vs Teleports--
If you're opponent see's your attempt to levitate, them might try to teleport. When this happens you can immediately cancel it and punish them according to the situation or the property of the teleport. Against KJung Lao you might just want to Uppercut, where as on characters like cyrax you can pull off a full standing combo. Or punish with a 2,1, df+4 mixup.
--Levi-cancel vs Parries--
This is all too common vs Johny cage players seeing as they have an parry x-ray.
when rushing down, mixing-up or attemting to punish. You can switch it up and bait a parry for a free punish.
Levi-cancel when you have a good idea they are going to parry and they will mistake this as an attack. While you can normaly do this by stance switching which is also nice for baiting parries. levi-canceling can be canceled out of strings, able you to block just incase it's not a parry you've baiting. Making it nice and safe. If you do manage to bait an parry or attack then you depening on circumstance you earned yourself a free combo.
--Levi-cancel vs Projectiles-
It's ver common that you'll fight an opponent with projectiles.
Weither trading projectiles or trying to punish, you can simply cancel and block a high projectile, or duck it. cancel and block a low, or jump it. or cancel and punish with a jump fireball, df+4, or hair whip depending on character and more importantly distance.
-Pressure: I've yet to see a Sindel player do this.
Usually when you're in someones face with Sindel, it can seem like your moves have slow recovery or that you can't keep them locked down anymore than 3 to 5 seconds. What i sometimes do is in the middle of combo strings levi-cancel and continue adding pressure. It's not as good as Kabal's combo into a run, cancel, repeat. But even though your opponent does have a chance to get away, punishig you will be tricky for them.
If they don't manage to move and you keep them locked down. you can follow up with a df+4, or 2,1, df+3 string. To be practical of course. You can follow up mutiples ways. But I find those most helpful.
Hope this helps.
I'm sure there might be more to do with it, but we'll see.