Without getting into the merits of the models design you should note that Conditional Formatting is super volatile - the sheer volume of rules in place is the main culprit.

To illustrate - if you run the below code (removes all conditional formatting) in a back up version of your file and then test the subsequent performance you will (I think) notice the difference.

Sub Remove_CF()
    Dim ws As Worksheet, xlCalc As XlCalculation
    On Error Resume Next
    Set ws = Sheets("0703")
    With Application
        xlCalc = .Calculation
        .Calculation = xlCalculationManual
        .EnableEvents = False
        .ScreenUpdating = False
        ws.Cells.SpecialCells(xlCellTypeAllFormatConditions).FormatConditions.Delete
        .Calculation = xlCalc
        .EnableEvents = True
        .ScreenUpdating = True
    End With
    Set ws = Nothing
End Sub
I suspect you can revise your rules if you need the conditional formatting but I imagine from my initial glance there are other gains to be had by virtue of a re-design.