Is Soul forced to be sequential?

Are you?
No, it is ok!
And it definitely is, if you are happy and content where you are.
 In my new book "And lead us into temptation or the benefits of a false prophet" I describe a development of beings of being basically not interested in the Life after or the question"Why are we here?"

Bad karma for the bamboo or its purpose?

I am not so sure if it is a linear development. If Soul exists outside of time maybe it is not a sequential process. In Germany we have an education system that basically is like a stack where one builds on the previous step. At least with me I observe a tendency to see things sequential.
How do you see it?
I easily can image that Soul passes through a sequence of OJTs (on job trainings)
Maybe there is a basic training which is sequential like high school. But then God places us in a "working environment" and gives us a challenge. At the end of the assignment we evaluate ourselves or are evaluated and get a new assignment or are sent to a special training that helps us to get more qualified. Then we go back to this job and do better now.
I can imagine this applied to priests who abuse woman or children in their flog or politicians who misused their power.
Did you hear about reincarnation therapy? It is a method where people with problems are guided backwards to the source of this problem, which often originates in one or several former lifetimes. Of course this technique also was ans is used by curious people who want to know about their karmic history. For me surprisingly often the people were kings, queens, knight, warriors but seldom was there a recall of a simple person a maid, a thief or more general a member of the lower class.
I agree it is easier to remember if it was a "big thing" than something small way back.
But what if we were a king or a barangay captain, a chief or maybe only a respected elder who misused his power and now came back to see the other side of the experience.
For me the universe does not act on wishes and karma is not for punishment.
When I was in training to become a craftsman we had to hone a flat area and had to do it again and again until it was flat and not slanting.
Yes, sometimes it felt like punishment, but that was how I felt. My master only wanted a nicely honed piece of work,
I really like the example of karma being a stick! We enjoy it when we can use it to beat someone and we call it "bad karma" when we experience the other side of the stick - the being beaten.
Maybe we start as little rulers, as the head of our family, If we do well we come back as the chief of a village, go back for a training and become head of a tribe.
Of course you can say this is sequential one life time after the other but it is not a steady spiritual evolvement reflected by a social status. maybe it is better to say for sure more comforting: Our social status not necessarily reflects our spiritual status!