Hi Max,
Not sure if you need to prepare 220 specs...
First try to segregate the BEx reports and see how many reports are there for each info provider.
Lets say X info provider consists of 10 BEx reports built on it, now try to analyze and see if you find any common things among them. Now you can club those reporting requirements into a single FS.
I am still a bit confused about the BI system FS/TS. Template has Info Area field with fields like DSO/INFOCUBES/INFO-OBJECTS .
For ex: You have a MP --> under it you have 4 Info providers --> in such case you treat this as a scenario and create one spec for this.Like this you can reduce the specs. In this case the whole scenario covers 4 ICs and 4 DSOs.
No need to create specs for each and every IO also, try to create Specs only for the major master data like 0MATERIAL,0COSTCENTER,0PROFITCENTER,0WBS_ELEMT etc.
Regards
KP