I have a very simple suggestion that might require a code change versus an numbers change.
My suggestion is that she not be able to enter her mech if she has taken damage within 1 second.
If Deathwing has to be out of combat to get into flight and Zagara has to be out of combat to enter Nydus why does Dva get a free cleanse after her E ?
Just a thought ? other idea’s to make dva less unfun to play against.
Your title says “less oppressive” but it should say “unplayable”…
I have to agree with Odin that this change would make D.va unplayable, because if her Mech is destroyed she wouldn’t be able to join her Mech ever and she already struggles, when her Mech is destroyed. For your change you would need to buff her pilot form significantly… Is that what you want?
You would have to get out of the fight call down the mech and re-engage. Its not too much different than her current play style she just has to find a safe place to get her mech she cant dentontate take dmg then get in mech using both health bars. It wouldn’t ruin her it would give the other team a fair chance to kill her.
I kinda agree, this would make her unplayable. Clunky at best. She just needs some tuning in either damage or survivability department.
I agree with the OP, it’s pretty ridiculous to see her jump into a mech again with people wailing on her, getting her down to 10% health, oh but too late. If she wants to get back in the mech, she can do her silly roll and find a place away from combat to do it.
No it is clearly not. How about you ignore the detonating Mech and just attack Baby D.va? The dmg from the detonation of the Mech is nerfed and it’s dmg is not really dangerous anymore, except you are Ming with glass cannon build… but then you still have blink…
Only against noobs, who panick, when they hear D.vas voice “Nerf this!” and they see the detonating Mech and run away like chickens and ignores Baby. D.va
On topic, if you want to nerf D.va like this, then you have to make her Mech detonation fearsome and stronger again, it is joke compared to the old one.
This would only make the method of sitting there until right before your mech dies before activating self destruct unviable.
But you’re supposed to use boost to send the self destructing mech at enemies. It’s sad how rarely I actually see that, because the other way is just good enough. It’s maybe too good.
I think there’s justification for what the OP says.
Though self destruct does have the longest cooldown of pretty much any other basic ability.
I will grant you that the explosion damage doesn’t feel all that oppressive anymore. I have been deciding to just deal with it rather than run away more often these days. 
Indeed that’s why D.vas instant cleanse is needed, because good players can ignore that detonation and attack her. If you want to remove the “cleanse” or what the OP said, then buff her explosion to be dangerous.
She can be fixed with a few number changes. This isnt it.
She’s always been annoying, nothing has changed. Strong or not, Blizzard decided to not change what makes OW characters what they are, utterly annoying. Even when you kill them you don’t get satisfaction.
Heroes like Genji, D.Va, Tracer, Lucio that have several ways to escape or survive death are despicable and annoying even if they’re not strong or OP.
This^
D’va feels oppresive because after a long wait she is finally useful. She needs some numbers adjusted for better or for worse but her main mechanics are fine.
How come Xul didn’t get this same treatment? People demanded his head like a week after his rework, fresh out of being a giant meme; 17 nerfs later he’s right back to that status.
Why does this forum just HATE the concept of Diablo heroes being actually useable anyways, outside of like Cassia and Valla.
people especially hate xul because he’s the only strictly diablo 2 only hero. talk about minority status