Definitely try booborbust, a too small cup steals from the band so you'll be surprised with the results! Also have a look at Molke bras, I've not tried them myself but had loads of people swear by them!
Please please try the boob or bust method it's changed my boob problems like you wouldn't believe. I was in a 42dd and I'm now 40GG and the constant breast pain has gone. I was measured several times at both M&S and Debenhams and told the 42 DD. Make sure you read all the blurb about how it works the lovely ladies there will also help with online fit checks https://booborbust.com/bra-measuring-guide/
I find these a really good ‘inbetween’. When I can’t stand to wear a bra but the outfit I’m going out in looks awful with a saggy croptop I use these www.marksandspencer.com/louisa-lace-bralet-dd-/p/p60105434?prevPage=srp It must be the DD+ ones (there’s a very similar range without the word Dd+ without so much support) and it actually gives me enough lift to wear a dress. Not as good shape as when I wear true scpholding but so much comfier