Of all these I think homework or portfolio is the most reasonable. I've almost never used leetcode style coding in my actual job, pedigree isn't indicative of much in my experience (all the best hackers I've known in 10 years and two continents are from eastern European state universities), and gut feeling is a coinflip.
Unless you also know a bunch of bad hackers from Eastern European state universities, it sounds like you're saying that pedigree is actually a great measure.
- LeetCode (and other tests)
- Homework assignments
- Looking at pedigree (university)
- Looking at experience (where you've been working)
- Looking at portfolio (open source contribution)
- Using gut feeling
Each has its drawbacks. So what is the fairest way to interview software engineers? I guess, we should let software engineers pick their poison and start from there.