It's one of those "nice idea, would never work in practice" things. You can pick so many holes in it I'm surprised there aren't photos of Kurt Cobain wearing it on stage.
Mainly what would happen is a huge market growing for players with low points ratings. There's no way a points system would be able to assign a fair rating to rookies, so you'd end up with massive bidding wars for people like Makasini. If there's no salary cap, or only a nominal one, you'd get ludicrous distortions like 19 year olds getting offered millions for short-term contracts then suddenly losing huge amounts of their market value when and if their points value goes up.
Then you have the problem of points values being recalculated, presumably, annually. What happens if you have a team that massively overperforms expectations and all the players' values go up, but a lot of them are on contracts that go longer than this year? The Raiders, for instance, would be massively over next season's points cap simply because they've been good. Now they're forced sellers: they get penalised for playing well.
As you say, I could go on all night. It's a completely unworkable concept, which is why no serious competition in the world uses it.