My preferred loop is:

15m recruiter screen (1hr Take home goes here if you’re doing it) 30m hiring manager call 1hr tech interview 1hr team fit

And a go/no go at that point. You can put the hiring manager call at the end if the hiring manager is a senior enough person that you need to protect their time.

The tech test should be actual code, but not evaluated for syntax. I like a code review test but we’ve also done problem solving and writing pseudo code in the past. No let code, no algorithms and no tricky formulas. If you want one of those you should provide the formula. A good tech interview should be open ended enough that you can dig into whatever direction the candidate goes - if they go hard onto concurrency then follow that track, or if they go into testing then follow that track.