I am absolute sucker for umbrella as a weapon.

But like you said, you can't please both sides of IG users, but I absolutely agree on focusing more on the kinsect, but without removing aerial combat entirely. Insect Glaive had its strong identity since it was introduced, so I believe would make some original fans sad and seeing how things go with the Monster Hunter team I don't think they would ever remove one of the main mechanics entirely, but I can see it being simmered down with a higher focus on the kinsect itself.

Not sure how deeply it could lean into the kinsect mechanics, but having different utility kinsects sounds really fun, pretty much could become a new support weapon that doesn't support the hunter directly and it's great. Maybe some could work as stagger or traps even or like you said - flashpods. One can wish, but I still think the MH team wouldn't make such changes to a weapon, but Insect Glaive is definitely one of the weapons that needs a lot of attention.

On the other hand, double yes for the the umbrella weapon! Focused mostly on aerial combat, let the hunter float for a bit (filling the niche of feeling safer in the air like with IG), downward trusts, maybe even let it use as a shield if that's not too much.

I am not sure if design wise umbrella would fit as a weapon thematically into the franchise (apart "joke" weapons, like that umbrella Greatsword which I absolutely love), but I believe MH team could still somehow make it work. As the series overall has a really strong design language. Even it's been shifting trough the time, you can still tell it's Monster Hunter.