I’d get it done ASAP. he won’t be in any pain (ours wanted to play hours after coming home). if he’s not shown any ‘unwanted affections’ towards inanimate objects yet, it doesn’t mean he won’t later and the longer he’s left to hump things the harder it is to get them to stop, even after the snip as it becomes a habit.
Edit: I highly doubt you’ll make what sounds like a fantastic dog into anything else!