Spelling and times tables should be homework as should reading.
Grandson has switched to a school, he is 9, and this is his only homework. However it is a new school, private and only 8 pupils so work is completed in class and he has improved enormously since moving schools. Grandaughter switched to an online school aged 12 so she can do her horse riding. She does have homework for each subject once a week, always due by the end of the following week. She finds this works well and it is not stressful. She needs minimal help and sets her own time table for this. The online school is great because if she has to miss a lesson due to horse shows the lesson is available as a video for a week so she can and is expected to watch and catchup