From recollection the feature I was requesting related to your leave request section.
To clarify, this request has nothing to do with the actual payrun and everything to do with leave request record keeping.
I never ended up using your inbuilt system because I did not want to risk screwing with staff leave accural calculations and instead have been tracking manually just adding in the used hours as part of the payrun leave section as you have mentioned.
In terms of what I suggest you add. Your leave request form currently provideds a projected leave based on the number of days requested at 7.6. Whilst its great this form auto calculates, the actual amount needs to be modifiable. You could do this by taking the ‘leave usage’ text line and changing part of it to a numbers field.
For reference, an example of leave request history tracking done well is
Quickbooks Your Payroll. I have attached a snippet for your review.