What could help in this case (cinebench temps) would be using a different LLC (Load Line Calibration) setting, this pretty much determines what's the voltage curve depending on the CPU load. Each motherboard manufacturer implements that a little differently, so I can't say which setting would you have to choose. Preferably the one that has higher voltage droop.
Honestly when applying a thermal paste it's actually better to use more than you need than less than you need, so applying more of it in general is a good practice. Your IHS may not be perfectly flat, but thermal paste should mostly fix that issue. Keep in mind that with Ryzen chips, and especially the current Ryzen 7 lineup you have only one, fairly small area that gets very hot - which is where the CCX die is. Here's a render picture, I marked the "hot" die over there:
The other die is the I/O die and it doesn't get nearly that hot. So you've got a very small, dense and hot area that's not in the middle, which is why proper thermal paste application matters a lot