I'm just gonna copy and paste what I had written before.
You clearly haven't played a D3 that knows the match-up.
D3 shouldn't be using his f-tilt if you already started your dash animation, it's supposed to be spaced so that it catches you at the start-up of your dash so you can't shield...and if your not running a perfect shield doesn't get you a grab on off of his f-tilt.
Inhale is also a factor on stage, just not so much but be aware that if you do get inhaled in he has invincible frames he can abuse to separate the IC's (just like any grab)
"Anything in the air" is dumb and will just lead to free hits for D3. D3's dair out spaces your uair so if he see's you going for it a D3 can just used those five jumps to out space you in the air. And if the final hit of the dair hits you or nana, your separated again. It's more of a bait and punish game when the D3 is in the air, bait the dair then punish with an aerial.
I'm not saying that it's D3 advantage (that would be dumb), but just know there is a lot more to the match-up then you stated.
So that was a response to another player in regards to the match-up. Match-up is not easy for D3 but he has the tools to play it. ICs need to bait and punish since playing aggressive on D3 even though it's an advantage match-up is a bad idea on experienced D3 players. If we look at serin's list
What we do:
Inhale
Dair
Retreating Bair
Fthrow (since it hits popo as well)
Bthrow (for separation)
All these tools D3 has have to be used defensively since all are punishable in some way. Baiting any of these options can lead to a grab and a stock. The retreating bair's are probably his safest option from this list (Approaching ones can be grabbed easily). The others, inhale can be punished if not landed, dair the climber player can wait for then u-air. His grabs are amazing tools when landed but when missed can equal a stock for D3. Jabbing out of grabs and inhale can lead to a grab for us.
To add to serin's list, D3 can also us waddle's to disrupt our ability to camp D3 with projectiles and D3's F-tilt is still a great spacing move when used correctly, goes through blizzard.
It's a bait and punish match-up for both sides, since if D3 lands the right move we are separated and punished. Vice-versa if D3 is baited into a certain move we can grab the lag of it or use up-air and our othe aerials to do some nice damage.
I personally use Fthrow>Fthrow and turn around w/ bthrow hobble for D3.