Sales Ledger - Customer Allocations

we have customers who pay monthly a batch of 40 plus invoices / credit notes....it would be really handy to highlight the selected payments which they have paid to then press the allocate key on one occasion oppose to the 40 occasions you currently have to do, or be able to double click on each line to add the total up in the bottom right, to then press the allocate key again on the one occasion when the payment balances.