This is a simple method to sequence the sessions in a workflow which is of flat loading (Without any transformation or all sessions having same transformations).
Input: The table name and average/maximum record count as input.
Ouput: The macro will calculate the number of levels and no of sessions in each level to have optimum load time.
Find the macro here https://drive.google.com/file/d/0B97Vr-6tYsyTOXgwU1J6M2NWdDA/edit?usp=sharing
Note: This macro wont consider the table size in terms of number of columns and also consider this as a non-professional code. Can expect some errors.