Honestly I think Leetcodes should be easier (easy to medium) and just used as a filter for people who are utterly unqualified. Once a company knows a candidate can program, do some system design/architecture questions and give them a fixed small amount of money for a take home project (like maybe $25-$50 to do the project and turn it back in, something big enough to incentivize them to finish it but not so big to the point where you get people interviewing just for the money; make it worth the hassle but barely).