We are at a similar place in our journeys, I think. This next IVF will be the last with our own eggs.
Improving egg quality is like the holy grail of IVF, it's very hard to fix, but protocols can be tweaked and may result in better numbers.
I would also suggest a 2nd opinion. Look at some of the bigger, well known clinics (SIRM, CCRM, Cornell) or clinics in Chicago or NY. Some clinics, depending on your state, offer a free phone consult - with others the charge is around $250 or so - which is well worth it to either confirm your doc's opinion, or find out there may be more to the story.
I believe that you should continue with the PGD. If you have another set of abnormal embryos, it will be a very very hard pill to swallow, but maybe you'll be able to move on to your next step (DE or adoption or whatever) with a better sense of peace about the situation.
We are in this same spot and having no normals after testing is one of my fears, but I also feel it will help us to move forward, knowing we tried our best and did everything we could.
Putting back more than 1 embryo in with unknown abnormalities (non PGD tested) could put any sticky normal embryos at risk.
I would not blindly transfer more than 3 embryos myself and frankly, will not blindly put back any of our own embryos again without testing. It's worth it to us to avoid another loss.
Big huge hugs.
Feel free to PM me any questions or just to vent.