Slight Buff Suggestion for Poppy

So let me preface this by saying I play a lot of , and I think she's one of the best champion reworks that Riot has done so far. She has clear windows of opportunity, and it's very satisfying when you can find them, but she also has her share of weaknesses, which I think means she's a pretty well-designed champion. Anywho, she seems to be struggling a bit right now - she's not picked very often despite having what I consider to be a very fun kit, and it seems she generally doesn't scale too well into late game. Based on my own experience, her main weakness is that without a good wall-stun, she doesn't have a very reliable form of engage in team-fights. This is totally fine, though as I think this is an intended weakness, and it's a good one to have. It makes it so that the Poppy player needs to cleverly position to start off an engage on an enemy champion, and it gives her opponents a chance to position so that it's a little harder for Poppy to find a good engage. One of her biggest strengths that isn't really shared by many other champions (at least not to the same extent) is her huge disengage potential - her ultimate being one of the most powerful disengage tools in the game if used properly. Another strength of hers is being able to survive quite well even at low health thanks to her buckler passive and the passive on her W (Steadfast Presence). All that being said, I think a good buff to Poppy to make her a little more fun and satisfying to play as could be one of 2 things.

The first is to make her ultimate channel uninterruptible by certain forms of hard CC (i.e. snares and roots) and/or refund more of the cooldown when interrupted. As a tank, you're generally positioned towards the front of your team which means you're more susceptible to the enemy team's hard CC abilities. If the enemy team finds a good engage, your first thought when playing as Poppy is to use your ultimate to try to save some of your teammates. Unfortunately a lot of the time this gets completely shut down by a rogue snaring ability (Jhin W, Caitlin Trap, etc.), and it feels kinda bad whenever it happens since it negates one of Poppy's major strengths.

The second good option I think would be to make her survivability at low health a little bit more pronounced either by increasing her base HP to be more inline with other tanks so that she has more health being protected by the W passive (potential problem with this buff is that she becomes too strong in the early game due to also having high base ability damage) or by making the passive on her W kick-in whenever she falls below 50% of her maximum HP instead of 40% as it currently is.

I'm interested to know what people's thoughts are on these suggestions, and of course if a Rioter would like to weigh with his/her thoughts (either agreeing or disagreeing with these suggestions) that would be more than welcome.