quanglewangle, so you have a 1/4 wave ground-mounted monopole antenna in a multi-band fan configuration with ground-mounted counterpoises for each band (presumably).
I would say all other things being equal, the only band where adding the height of the berm might be marginally noticeable, is 10M, since 3M of height is ~1/4 wavelength; the other bands will likely not see any difference due to the increased altitude and potential of "blocking" your radio wave.
The thing that might help by being on the berm, is not having a "good Earth ground", and therefore reducing ground losses, in other words, not having your radiator too close to Earth, but again, this may only make a difference on 10M. Also, I'm not suggesting you don't ground your antenna's counterpoise, but I've read that in the USA, single-point grounding to your home's utility ground, via an independent conductor, is the proper way to ground for lightning protection, but not RF purposes; however, if your coax is on the ground anyway, you may already have fairly good elimination of stray RF on the coax shield, through capacitive coupling with the Earth.
One other side-note, since your counterpoise elements are 90 degrees from your radiator, this should mean that your input impedance at your resonant frequency on each band is ~37 Ohms, which means your best VSWR on each band is 1.5:1, and when you're operating away from your resonant frequency, your VSWR will only get worse. I might suggest a 1.5:1 UnUn if that is your "best" VSWR, whether or not you move the antenna. This guy on eBay https://www.ebay.com/usr/hifi1200 has had 1.5:1 UnUns in the past that I have purchased and found were excellent quality, he currently doesn't list any now, but you might try contacting him if you can't find one anywhere else.