This isn't a terrible idea
The main problem many will have is cutting the number of immigrants down, but that's something a lot of conservatives have run on so it was to be expected. If you ignore that part of it I think the points system is the right way to do it. Obviously you can quibble with it in terms of what 'x' should be worth, and I think it would work better if there was a threshold of points above which we'll take anyone who wants to come instead of having quotas, but other than that it is a good start.
The salary thing is rather like what I've been saying for years we should do to fix the H1B, except I'd link it to percentages of the average salary in a given location. 300% of the median US salary is a lot less than 300% the median salary in San Francisco or Manhattan. The H1B is terrible in all ways - it lowers salaries of tech workers, is a gigantic pain for companies to bring in employees, and removes the freedom of H1B workers to seek a better job without losing their green card.
From what I hear on the news (the "fake news" for you Trumpists) the bill as it stands has no chance of passing congress, but if they took away the hard limits and made them point limits, and tweaked the points, If expanded to cover more cases, it could simplify US immigration policy by subsuming a bunch of different <letter><number><dash><letter> coded programs into one via the points system. If it makes it more expensive for Trump to import maids for his resorts...well boo fucking hoo!