I think that simplifying the ability score system is a magnificent idea. There really is no purpose to the current method, which just has numbers for the sake of numbers. However, the 0-5 scale abstracts things too much. The stat bumps at 4 and 8 don't transfer, and you lose the ability to place 13s (which is useful apart from feats in a lot of cases). Also, the following chart doesn't work:
1/1
2/4
3/9
4/16
Under this system, you could get a +4, a +2, and two +1s, but in 4e if you get a +4 and a +2 you don't get anything else. Might as well be consistent: +1 should cost two points and +2 should cost 5.
1/1
2/4
3/9
4/16
Under this system, you could get a +4, a +2, and two +1s, but in 4e if you get a +4 and a +2 you don't get anything else. Might as well be consistent: +1 should cost two points and +2 should cost 5.