thanks for posting the info on the cribs. It's always good to see others ideas on what's available to safely work on a car.
Regarding jack stand and related adapters to fit the slots on the jack points, I've found that hockey pucks work extremely well, as is (fit between the jack point and the stand). They are durable and "mold" themselves if placed on the stand properly.
My car is not lowered (sport suspension) but my jack still has trouble getting under the jack points. My best solution would be to buy a lower profile jack but i've improvised two ways:
1. Rhino ramps, similar to the ramps you show, then jack the car. This usually works but they often slip trying to bring the car up.
2. 1/8" vinyl tiles. These are available at many home improvement stores. Using 4 to 5 of them, I can quickly raise the car a 1/2 in which is enough to make the jack fit underneath. The tiles are also good to use if you need to make your car level in an un-even floor or to make temp adjustment to alignment toe. Credit to CALWATERBOY for giving me this idea and the following video link....