You use breast compression as soon as she starts nibbling, and I think you may have a latch problem.
I know you may have been told your latch is perfect but your nipples shouldn't be so sore you can't BF after a cluster feeding. Which leads me to believe you could improve your latch. Another hint is that she nibbles so much, if she isn't latched on well, she may not be getting adequate milk flow causing her to nibble rather than get a whole mouth full of milk.
To begin with, do your nipples ever look like a tube of lipstick after you BF? By this I mean, when they are pulled out from nursing, does one or the other side have a slant or angle. This is the first sign that a latch that may look perfect is too shallow. This is one sign but not the only one that someone has a lath problem.
Also, I know a baby led latch is recommended by some, but I think you may want to take more control over her latching so that you can ensure she gets a deeper, more effective latch every time.
Some resources to help:
https://www.nbci.ca/index.php?optio...5:when-latching&catid=5:information&Itemid=17
https://kellymom.com/ages/newborn/bf-basics/latch-resources/
I find the animated latch on the top of the second page super helpful in showing how to latch baby on.
Another thing that can lead a baby to have fussy, shallow latch is how you hold baby's head. To begin with, many moms want to gently cradle baby's head, cupping the back of it and gently offering the breast, moving breast to baby. You should ALWAYS have your fingers supporting her neck and not the back of her head. Babies don't really like the back of their head touched so doing that can cause them to fuss a fair bit and not be able to find a comfortable latch. The other thing I'm sure you've heard before is always bring baby to the breast, not breast to the baby. It might seem a bit rough, but when baby is hungry, make sure her mouth is open very wide like a yawn. You can do this by gently stroking nipple from nose to chin over her mouth. When her mouth is at it's widest point, supporting the back of her neck with one hand and holding your breast in the other hand(cupping it so that your hand forms the c shape) Quickly press baby to the breast as seen in the latch animation on the second page.
Don't give up yet- you are doing so good!