Compiled data of 113 runs:
I have found the 6k runs by far the most consistently profitable. The 100 runs are typically very good but the 6k runs tend to yield more then enough to make up the difference and require less micro managing.
Have not done many 70k runs after initial testing so they could have been improved. The 6k runs also could be coming out of a down turn in the balance cycles right now.
Source: https://www.reddit.com/r/EscapefromTarkov/comments/edz13d/yet_another_scav_case_data_set_post/