Custom spreadsheet solutions which survive long after the developer has "left the scene", are often those which users accept because they discover it _ among other benefits _ makes their work quicker and easier to do. That is why the best person to develop such solutions tend to be one who works in that area, and is therefore familiar with the way the manual system operates. S/he would have an "insider's" perspective of the best way to introduce automation other users will readily adopt _ even as it solves the identified problem(s).
For the purpose of creating custom financial and business management solutions that solve your identified problems, and give you control/ownership, without burning a hole in your pocket, Excel VB offers an amazing variety of possibilities, in the hands of an adequately skilled user.
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.
Automating Your Spreadsheet Document : What is Excel VB? Microsoft Excel is a powerful tool for recording, organising/re_organising, analysing and presenting information. By Excel VB, I refer to Excel VBA _ where VBA means Visual Basic for Applications(VBA). VBA refers to the highly extensive and flexible macro programming language developed by Microsoft for use in their MS office applications _ Word, Power Point, etc.