Honestly, even if we still have to deal with this AccessDatabaseEngine.exe garbage I still think your EPPlus stuff is wonderful and will definitely use it.
With SoftArtisans ExcelWriter, you don't need anything but standard data sets and data tables. Again, can be expensive, but if you are doing a ton of Excel automation and need full control (formatting, freeze panes, etc.), you save money in the long run. Additionally, it has 32 and 64 bit versions and likely can handle any scenario you throw at it.