I was messing around today, and I noticed that over 28%, the stun effect of dsmash cannot be interrupted by the first two hits of the jab combo. Thus, if you're fast enough, combos such as Dsmash --> Jab --> Plasma Whip are possible, doing 32% damage. Thus, if you can get off a dsmash, don't just think about grabbing, think about what you can do with a jab in there.
Note that this effect is not present in the Paralyzer, at least not at percentages that are practical.
Another thing I've noticed is that bair has a fairly decent hitbox right around the becoming area where Zamus' thigh meets her hip, which does 1% less damage (12%) and has roughly the same knockback, but in the other direction, not unlike the backwards hitbox in Sheik's fair from Melee. This isn't necessarily the safest option, but it's something to keep in mind if you find yourself in need of it.
Note that this effect is not present in the Paralyzer, at least not at percentages that are practical.
Another thing I've noticed is that bair has a fairly decent hitbox right around the becoming area where Zamus' thigh meets her hip, which does 1% less damage (12%) and has roughly the same knockback, but in the other direction, not unlike the backwards hitbox in Sheik's fair from Melee. This isn't necessarily the safest option, but it's something to keep in mind if you find yourself in need of it.