"I just wondered if you had to recommend a set up to someone (who wanted a nice stereo), would you consider cabling to be essential in your build price and your recommendations? If so, would you consider the cost of the cables to be on par with the cost of a component?"
I think cables can be very, very important.
But they are not essential, in that, you could use the stock cable and still play music. You couldn't play a record without a table/arm/cart. So, the table is essential; the cable is not.
Of course, it also depends on this "someone". Are they a new to the hobby? Do they have the funds? How patient are they?
I'd tell them to get the best gear they can to start, use the stock cables and then slowly upgrade the cables when they're able to. So, they should absolutely assume new cables are in their future, and therefore, start saving. Because they can truly, significantly enhance the experience when they upgrade--and it's a fun way to learn the hobby.