Even if you raise the tree limbs up to let sun in you will still have trouble with the grass because the maple has very shallow densely growing roots.
I would leave as many as the lower brances as you can, to benefit the tree. Then use bark mulch in the area where the grass does poorly. The mulch will decompose over time and become excellent food for the tree, and ideal environment for micro-biological activity...ahh, the circle of life.
Remove the limbs that poke you in the eye, but consider leaving as many of the others as you can. Don't you want nice shade on the patio come the dog days of August? The tree wants shade on it's roots.
The growing conditions that are favorable for grass, are bad for trees. Grass out competes the tree for nutrients and water. Grass also dries out soil which in turn reduces populations of benificial mychorizal fungi, with out which some trees slowly die. Lawn mower and string trimmer damage is a major cause of tree death. I could go on and on with reasons to leave the lower limbs but I don't want to bore you to death, just convince you to remove only those limbs that need removing.
