The points scheme was actually not too bad, but used in conjunction with the salary would work. You would expect the points to pretty much coincide with salary negotiations, but the issue with the old points scheme was that the fact that points were a little too rigid. Some players were classed as 7's and were only really 4's, but some 4's were 7's. Then there was the appeal process etc..
Rather than rely on points per say, it would be better for teams to work out their rosters, then work out the player points for that roster. If the points exceeded a set limit, then that team pays the "points tax" which the league could spend.
For example, under the old system I think the limit was 75 points per team. Let's say a team has the money to assemble a stud team of players and their points were 90, and let's say a budget club assembled a team of up and coming players for 50 points. All OK under this scheme, however, because the stud team points exceeds 75, then the league collects a "tax" of $X per point.
In order to get the points ranking per player, having a round number was restrictive so it could be out of 100 points per player, or if it was out of 10, make it decimal points too. I would say the league knows the "value" per player, so in setting the points per player, past performance etc could play a part, but also the club could potentially nominate the player value with other clubs having a say to ensure fairness (eg you would want a club saying that their player was worth 5.7 points, where in fact other clubs knew they were worth 7.3)
Points equalise the talent, whereas a salary cap ensures financial stability.