HI,
Presently, me too in the same analysis in our company.
43 Millions is huge number in Aggregates. This is as big as Cube data. Aggregate should always be smaller subset of Cube.
Your SAP_INFOCUBE_DESIGNS report is very dangerous now. Ideally the Dim table size should not cross 20 - 30 % of Fact table size. Yours is gone much ahead than Fact table size. there is huge scope to improve your star schema design. Dimension which has only one char, can be marked as Line Item dimension. Split your dimensions into multiple but not crossing 16.
Regards,
Suman