The savings _ from using your "in house" expertise _ in terms of money and man_hours alone, will quickly justify the investment you make in "developing the needed skills" _ especially, when you compare what you spend with the cost of purchasing a commercial software application _ or even engaging the services of an Excel VB developer.
The visiting head of the technical function only needed to look at the most recently plotted point on the chart (relative to preceding ones) for a Key Performance Indicator like. Cost per Hectolitres brewed(One Hectolitre = 100 Litres), to know if the brewery had stayed within the approved upper limit of spend(plotted as a straight line target across the same period) or not. Discussions would then take place based on identified "Exceptions"(which could be "good" e.g. savings made or "bad" e.g. monetary loss due to materials over_used), and "Actions To Be Taken" to correct or maintain observed performances agreed upon.
"Over_used/Over_spent"(Losses) and "Under_used/Under_spent"(Savings) _ on a monthly basis based on data entered, the program also automatically plotted charts showing trends over a 12 month period.
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.