All I ask for is shortened invincibility. I hate resorting to ledge camping or risking a cross up just to avoid an invincible opponent. Especially more so on smaller stages.
Invincibility is already shortened somewhat due to how Brawl handles it compared to Melee. In Melee, invincibility "ate" hitboxes such that if you were hit, the hitbox of the attack would be deactivated and you wouldn't be hit if your invincibility ended during hitlag. In Brawl/PM, invincibility doesn't do this, causing you to be hit during hitlag
even if you took the hit while you were invincible.
Also, it's possible to out-play and bait opponents while they're invincible; it isn't PM, but
Mango does this a lot when playing Hungrybox. Baiting people into bad positions during invincibility is critical, so I wouldn't want to see it shortened. 2 seconds is enough for the respawning player to gain back stage control, but it's also short enough for them to be punished for recklessly approaching by the defending player. This is just IMO though and not the official standpoint of the PMBR, others may have different viewpoints regarding this topic.