As far as a full curriculum goes, I don't believe there is one that does exactly what you want. Books (in the United States, at least) divide into two camps:
"Constructivist" (e.g. Everyday Math, Connected Math)
"Traditional" (e.g. Saxon, Singapore)
Now, any search you make that even has a whiff of these terms will summon up loud and angry missives (try this article from the New York Times for an idea).
Constructivist curriculum is an attempt to catch the "joy of mathematics" approach to learning; for example rather than a worksheet with addition problems there might be a question about all the different possible sets of numbers that add up to 20.
The downside (as pointed out by the article above) is that (especially when taught by teachers who aren't themselves strong in mathematics) it can lead to basic skills being missed.
This is a problem Lockheart's Lament acknowledges. He seems to think students won't miss anything important. This can be true if the person steering the education is a mathematician, but with a non-specialist (i.e. most elementary school educators and homeschoolers) things can go horribly wrong.
Now, it's possible to balance to pull off a fantastic curriculum, but the ones I know about (say, at the Russian School of Mathematics in Boston) are, as self-described by the teachers, not following a curriculum at all. That's great if the teachers are experts, but put homeschoolers in a quandry.
I think the world is still waiting for an inquiry-type elementary curriculum that can be followed by non-experts and doesn't shortchange basic skills. So for now I'd suggest:
a.) Pick a traditional curriculum (Singapore is fine, although do shop around).
b.) Supplement. This very question is filling with lots of suggestions.
It may not suit your goals, but one approach is to enroll in a masters program before entering a doctoral program. This could help you get back into the groove of academic life,
and also give you a chance to meet new professors who could write letters for your application to a more high-powered doctoral program. (I once advised a student who had spent quite a long time, maybe 8 years, in the software industry before returning to academia, and
this is the route she took. I think it served her well; because of the masters, which involved a mixture of coursework and a small thesis, she was very solidly prepared for her doctoral work, and was one of the strongest students in her cohort.)
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Marie desJardins has a nice article on Surviving Graduate School that is definitely worth reading.
The top two pieces of advice I would give are:
The most important thing when choosing an advisor is to find someone who will go out of his or her way to help you succeed, not someone who is famous, and not even someone whose research is in the right area.
You need to make the transition from being a mathematics student to being a mathematician. That means thinking of mathematics as an arena where you seek out unsolved problems and obsess over them until you solve them, not as a vast sea of material to be learned. Don't get sidetracked trying to learn everything; that's impossible. Focus on finding an open problem you can solve, and solve it.