I think too many vets "assume" clients won't stagger the vax schedule, out of convenience (e.g., if rabies, 5/1, bordatella and lepto are all due, don't assume I want to do them all in one appointment "for my convenience" -- I don't!).
When I raised the issue of wanting to wait 2-3 weeks between vaccines, my vet's eyes opened wide and he was surprised -- but he was delighted I mentioned it, as he prefers doing it that way. He stopped suggesting that b/c too many clients thought it was inconvenient to keep coming back. I strongly prefer it, but I was surprised that I had to be the one to bring it up and have a notation added to the file to never give my dogs a load of vax all at once. Everyone knows it's better for the dogs, so why isn't it the standard of care?
From the client perspective, not enough info is given to people about why rabies needs to be done as required by law. Once people know that for a minor, even accidental, nip, the dog can be euthanized and have its head cut off in the jurisdiction where I live, they get serious about not letting rabies lapse. I'm surprised vets aren't getting that information out about theconsequences for unvaccinated dogs in the event of even an unfounded accusation of a bite.
The cost of titer testing probably needs to be addressed. It can be very, very expensive.