Code optimierung beim starten des excel Files

Private Sub Workbook_Activate()
Application.ExecuteExcel4Macro "Show.Toolbar(""Ribbon"", False)"
Application.DisplayFormulaBar = False
End Sub

Private Sub Workbook_Deactivate()
Application.ExecuteExcel4Macro "Show.Toolbar(""Ribbon"", True)"
Application.DisplayFormulaBar = True
End Sub

Private Sub Workbook_Open()
ActiveSheet.Unprotect Password:="123"
Sheets("Rechnungen").Select
Range("C15:C15").ClearContents
Application.Goto Reference:=Worksheets("Rechnungen").Range("A15"), _
Scroll:=True
Dim wks As Worksheet
For Each wks In ThisWorkbook.Worksheets
Call wks.Protect(Password:="123", UserInterfaceOnly:=True, DrawingObjects:=False, _
Contents:=True, Scenarios:=True, AllowFiltering:=True)
Next
Worksheets("Rechnungen").ScrollArea = "$A$1:$AQ$450"
Worksheets("Mahnungen").ScrollArea = "$A$1:$AQ$120"
Worksheets("Kunden").ScrollArea = "$A$1:$X$147"
Worksheets("Daten").ScrollArea = "$A$1:$AQ$250"
Worksheets("Mitarbeiter").ScrollArea = "$A$1:$AQ$124"
If TypeOf ActiveSheet Is Worksheet Then _
Call Workbook_SheetActivate(ActiveSheet)
End Sub

Private Sub Workbook_SheetActivate(ByVal Sh As Object)
ActiveWindow.DisplayHeadings = False
Select Case Sh.Name
Case "Rechnungen", "Mahnungen", "Kunden",
ActiveWindow.zoom = 60
Cells(6, 2).Activate
Case "Daten",
ActiveWindow.zoom = 63
Cells(6, 2).Activate
Case "Mitarbeiter"
ActiveWindow.zoom = 62
Cells(6, 2).Activate
End Select
End Sub