If you never plan on moving to a full frame body, then sticking with crop lenses are liable to be a smart path to take, because the lenses will be as sharp, be less expensive, smaller, and lighter. Most EF-S lenses have much more modern designs than their full-frame counterparts and the smaller sensor size means that the correction requirements for full-frame, which is why L lenses get so big and heavy and expensive, are often loosened. You get a better, simpler lens for less money.
I.e., consider the EF-S 17-55/2.8 instead of the EF 16-35 f/2.8L II.
If you plan on imminently moving to a full frame body, then sticking with full-frame lenses is probably wisest with the single exception of the ultrawide lens. With ultrawide, you cannot find any lens that's going to fulfill that role on both crop and sensor, due to the nature of how the sensor format affects the field of view of any lens. In this case, go ahead and get a crop ultrawide. They typically hold value well for resale, and will cost roughly half what a full-frame ultrawide will (e.g., $600 vs. $1000-$1500).
I.e., consider the EF-S 10-22 (or Tokina 11-16/2.8), and then sell it when you move to full frame to help fund an EF 16-35/2.8L II or EF 17-40 f/4L.
Lenses like the EF 17-40/4L and 16-35/2.8L can be used as walkaround zooms on crop bodies, but keeping them for full frame use doesn't mean you'll have a walkaround zoom on both crop and full frame. It means you'll have a walkaround on crop and an ultrawide zoom on full frame, and you'll probably still have to supplement with 24-70 or 24-105L when you get that 6D you're lusting after. And the 24-x L lenses aren't quite wide enough on a crop body for walkaround usage.
When you format switch from crop to full frame, every EF lens you have will get 1.6x shorter. Do the crop math backwards to see if that lens is going to be a good fit for you on full frame as well. I happily used a 24-105 f/4L IS USM on my XT and 50D for years, but only understood what it was really designed to be when I got a 5DMkII. And now I want an EF-S 15-85 IS USM for my 50D, so I'll have "the same lens" on crop. And a 70-200 is going to look on a full frame the way a 44-125 would look on your crop body. Maybe you'd wish you spent on a 100-400L instead.