I believe using either of these two applications should not pose any problems for implementing your spreadsheet automation ideas. This is because both have always been "friendly", towards making it easy for users to get more functionality out of them by way of custom programming.
I believe the foregoing are compelling justifications for choosing Excel Visual Basic over Visual Basic.
This last point in my opinion is ONE major benefit you must seek to extract, if you choose to engage the services of a developer. S/he should be able to help you develop (in_house) expertise needed to maintain the application AFTER s/he is gone. If you fail to ensure this, all your cost_savings from using the application might end up being spent paying the developer to maintain the application over time in the future!
So, (when considering the automation I speak about) do not think about spreadsheet documents containing one or two click_able buttons that allow a user print a page or copy some cells from one sheet to another. Instead, I want you to picture an application(or Entreprise Information System) that customises the appearance of your spreadsheet workspace(to take advantage of maximum screen capital available on your PC), and offers you custom "floating" data entry forms.