Azure SQL Elastic Pools - When to Create a new one versus upping the eDTU?
It seems that you are below the limits in both cases, so it seems pretty the same.
These are the limits:

As you can see, the only thing that really seems to matter in your case and that donsen't double when you switch from 100edtu to 200edtu, is the max concurrent sessions.
So, if you are far below this limit, I suggest you to choose basing on the easiest design.
If you are reaching the session limit per pool, it's better to split it up in two 100 edtu pool.
Don't change winning team. :-)