Over the years I have done all of these three ways on different properties. You have a good grasp of the situation and are right on target. The weep holes will reduce the hydrostatic pressure on the walls (maybe not as much as the exterior french drain) and the water pressure is what causes the walls to tilt. Basically, do what your budget can afford -- it is more important to have some kind of drainage system than to take years to complete the best possible alternative. If you go with the drain buried under the floor, be sure to drill weep holes through the foundation/basement walls. I do this low enough that I install PVC pipes between the weep holes and the drain, and then cover the whole works with the new concrete floor. Feel free to e-mail me any questions you may have.