I found that creating an Acad Table via the COM, with hundreds of rows, is ... not workable - slower than slow.
What about AcadTable.RegenerateTableSuppressed property?
AutoCAD ActiveX and VBA Reference say:
Recomputing large tables consumes a lot of time and memory because the Table object is reconstructed from scratch.
To avoid performance problems, you should temporarily disable the regeneration of the Table object when modifying large tables through the VBA APIs, then apply the modifications and re-enable regeneration.