I used to be a sales manager in a previous life, I now teach SEN but have worked in a mainstream primary and have friends that are secondary teachers
Work/life balance (in my experience) gets better the longer you teach -planning in your first couple of years can be incredibly time consuming as you have no back catalogue so to speak, everything is done from scratch and can take an age
Marking depends on your school's marking policy but in primary can be 90 books a night, 4/5 nights a week -it's not a quick job
If salary is a major concern then look at secondary -anecdotally there are more TLRs available in secondary than primary
Having experienced the extended working week in sales, the lack of holidays one year I got 4 days off in the school holidays in total and the inability to attend school events due to staffing constraints and commission period deadlines, I find I have a much better balance in my life.
More importantly I'm doing something I'm passionate about
Could I earn more in sales? Absolutely -but life isn't all about money