And in answer to the question, 400,000 miles will pretty much get you whereever you want (with *A subject to availability) in any class that you like with those miles.

As you have enough miles, you could whisk Mrs Moon away on a full miles redemption ticket in Lufthansa First Class. Personally I like Bali a lot, so a redemption to Asia and onward to Bali could be a nice choice. Likewise, Cape Town is a great destination too.

Perhaps a mix and match redemption is a good option to compare a couple of carriers. LH in F on the way out and back on South African or the likes of Thai or Swiss depending on the route.