Redundant text and ability to customize

I would like to be able to delete the word Invoice from Invoice Number, Invoice Date, Invoice Amount.  The word Invoice already appears in large letters above, so this is redundant.

Also, rather than comments, I would like to call this Details.....  

Our company provides services, not Items, and I would like to have the heading read either "service provided" or Work Description".  This would be more accurate in my case.

I also don't have the need for the subtotal line:  it is redundant.

I would appreciate help on this.  IE, more ability to customize.  You have a great product otherwise and should make our lives much easier.

Thanks.