As always, there are advantages and disadvantages to both. I've only experienced whiteboard coding (and in a limited fashion), but I'd prefer interacting with an interviewer and getting instant feedback compared to submitting a lump of code and potentially never hearing back. Communication is something key they fail to measure with this type of interview.

I've never done a take-home either. I'm perfectly able to "pass" a whiteboarding interview, but I just find them kinda lame when it comes to actually evaluating skill.

I think pairing the take-home with the in-person interview is a nice compromise. Assuming you didn't turn in complete crap code, they can call you in for the interview and you can talk through your solution and why you made the choices you did.

Another possibility is to make the take-home a part of the in-person interview, and just give the candidate a laptop and internet access and a few hours to work on it, with an interviewer at hand to answer questions. The downside of course is that everyone gets less time just talking to each other. A plus is that this timeboxes the possible assignments so things don't get too crazy, and also weeds out people who can't complete it in that time (which could be bad, too, I guess).

Our current assessment is about 4 hours and i think that's too long. When i was hired I remember multiple points where i seriously considered giving up. O can't help but think how many good people we lose to an excessive applicant process

Serious question, are you not also concerned about the poor quality of worker you might take on with a less rigorous process? I think I'd accept a few false negatives to avoid the hassle of false positives (in the UK at least, where employment law protects employees above all else and people can be very hard to get rid of if they want to be).

UK has trial periods too though, or? I've been in trial periods from 3 to 6 months, which is ample time to find out if the hire was successful. It's of course still very bad to fire someone during the trial period though (for both wasted effort and employee morale), but there is that option.