Higher marginal income taxes discourage investment and productivity and high capital gains causes high distortion/is difficult to implement/also discourage investment. Affordable housing shouldn't be tried to be solved by throwing money at it (subsidizing demand), the real way is to cause the supply to go up by laxer zoning and less restrictions. Inheritance taxes could also be used to 'level' the playing without causing huge distortion. Another good tax would be land value tax which would end up taxing those with more wealth the most as well as causing less speculation and more investment in actual companies which would fuel economic growth.

Better unions will never work in the US these days because of deindustrialization and globalization, can't really have leverage when your sector is getting smaller. There's also just no more 'union culture'.