I have had this problem since I have needed to wear a bra every day. When wearing a thin top, my bra strap buckles have often been clearly at the top of my shoulders, instead of down my back, as is the case for normal women, and they do notice the difference!
Here are a few ideas, not necessarily solutions, though.
Firstly, try going down a band size and up a cup size. Bra strap lengths are often related to the cup size. If the bra band is too tight, you can use an extender until it stretches. You may also be surprised that using "swoop & scoop", you can actually fill the larger cups.
A larger cup permits you to experiment with chicken fillets, and, as a regular breast pumper, I find the cup room is useful for wearing nipple shields and nipple pumps.
Finally, try a multi-way bra. You may not be able to wear it cross-strapped (although if you can the extra support is nice!), but the straps will be longer, making conventional bra wear easier.
The problem is that the bra straps are attached by plastic hooks, which can ping off, and the front fastenings are often too far apart, leading to dropped bra straps.