Boil it down. I think I understand what you are saying and then just as quickly I don't have a clue.
If you can throw $10'000 on glass, but you cannot justify spending more than $500 on a body, then you are being unreasonable. APSC sensors are only using 40% of the L glass potential. Even if you only got 3 or 4 lenses and use them / love them equally, then each one will only get a quarter of your attention, while the body is used for 100% of the time. If you worry so much about the resale value, then why not buying used bodies? I'm sure about one thing - I should have bought a used 5D with 50/1.8'II instead of a Rebel with some zooms (for the same price). Yes, I'm not one of those "covering the range" people.
I think that there is a conflict between two topics - "lenses before body" and "FF vs Crop" - which shouldn't be merged. However, when they do merge we get "$10'000 of L before FF" which sounds like "marriage without sex", or "FF with only $8000 of L" which sounds like fun (and the right way to do it), or "FF before any L" which sounds like "sex before marriage" (kinda fun too , for a hobby).
I don't think I was saying you should never upgrade your body... but with limited funds and the presumption of good light, you will be better off with a crop sensor plus s good L lenses versus a full frame and a 28-135.
Not to long ago a guy was asking if he should get a5d mkiii to pair with his 70-300... and everyone but me said Heck yes... I don't know if I'm clairvoyant, but I eventually got it out of him that his lens was a 75- 300, which is one of the worst lenses canon makes.
So with the money, I'd rather spend 3000 on a 24-105, a t3i, a 70-200 f4L IS, and a 580 ex ii over the full frame alternative. And with my math... I still have enough for a tokina wide angle or some nice primes...
Full frame is great... but you really should have some lenses to complement it.
As for resale value... yeah... that's the only way I can afford being in photography.
If I buy a lens for 1000, use it for 3 years and then sell it for 850, then I rented the lens for $50 per year... which in my opinion ifs well worth the effort. But more often than not, I buy a lens for 700, and sell it for 850... so they pay me $50 a year to keep their lens warn and in good condition. And I'm happy to oblige.
Somehow most people think that FF is only better for low light and that it is the only advantage over APSC (or maybe they don't care about the rest), while there is actually much more than that (at least 2.5x more). Same people are most likely to support the in-camera JPG propaganda, because they don't care about the difference. If you take 5 different cameras (different brands) and get it all right in camera for shooting the same scene, you'll still get 5 different photographs. Then what? Choose the one you like best and declare all the rest a blasphemy? But do you remember that you did everything right in each camera? That makes no sense. Let's do science, not religion. 24-105L on 6D won't scream "you need something wider!".