By digging holes, essentially you're 'drawing' the water to the path of least resistance. Assuming the water isn't rising straight up from the ground, say from an underground spring, then you might have better luck with a perimeter drain. With this, you could either 'collect' the water, or if you have slopage, let the water 'run' away from the foundation.
If you want the simplest method to alleviate (not eliminate) your problem, don't dig any more holes. IN fact, fill them. Then, lay the plastic down and throw some bricks or something around the perimeter in places. Make sure the plastic is right up against the foundation wall(s). Yes, insulate the floor with R-30 with the Kraft side UP. (Just go in the crawl and gently 'push' the insulation in between the joists.) Then, run string or staple up chicken wire on the bottom-side of the joists. Yes, let the insulation 'collapse' down. (The chicken wire will hold the insulation in between the joists.) Don'T staple any plastic to the joists. You shouldn't have to run the dehumidifier but let it run as it will 'show' you how well you did. Don't forget living in the house generates a lot of humidity. SHowers (long ones for sure), cooking, warmth, and so on will draw moisture into the living space.
Feel free to search the Forum page for keywords like 'crawl' and 'basement' and 'moisture' for other information and posts very similiar to yours. Other than that, my best to ya and hope this helps.