My advice is- its not the sort of car to own unless you're prepared to get the spanners out occasionally. Had my one 13+ years now and it's a great tool. But does need fixing here and there. Age/mileage irrelevant as if it's old everything that will go wrong has done so already.
New hub. Comes with sensor all lined up and ready to go. I bought cheap as poss through a decent website. I did have one fail within a year, but because of where I bought it they exchanged it for free.
(Purchased June 2013, exchanged Jan 2014 fine since. That was JGS4x4)
And if it stops leaking, it's run out...
As long as everything oily is "serviced" regularly (ie checked/changed when it should be) you'll be fine. (Eg engine, 2 x diffs, transfer and gear boxes at least)
Sorry I don't know about the modified oil breathers.
Looks fairly normal to me. Mines always "leaked" everything from everywhere and has had an oily undercarriage forever. Have you checked levels to see if anything is actually low on oil?
A little oil goes a long way, I wouldn't be too bothered myself.
I've got roughly the same age/mileage as your advertised one and owned it from 4K on its clock. Mines more basic so;
No Ace- don't notice not having it
No sunrooves- still leaked from new!
Air suspension- fab for towing
It is so different to a freelander its not funny.
I had many many...
"Usually";
You get the 3 amigos
You get the fault read and reset
You get the 3 amigos again before your new hub turns up
You change the hub
You get the fault read and reset (and have to drive over 15mph to clear the abs light)
Then your fine.
Stake nuts are CDU1534L and front and rear are all 32mm (if you have and use the correct nuts, which I'd say is likely!)
I bought a big torque wrench second hand on eBay. Used it 5 times now so paid for itself in money saved on diy hub changes!
Eg http://www.rimmerbros.co.uk/Item--i-CDU1534L...
Mine hasn't got ACE, there's no cruise control, no heated seats, no folding mirrors, no parking sensors, no sun roofs, no leather moving seats, no cdl and no cd multi changer.
Don't miss any of it.
I had a fault (on my other car) on the alternator and it was spiking up to 18v occasionally. Blew 2 headlights while it was faulty which I presumed was down to the over-voltage.
I have a little volt/temp meter that plugs in the cigarette socket, so I could monitor while driving along.
I've done 5 now. Totally diy, done on the drive. Buy the proper tools ffs, they will come in useful again! All the adding pipes on the end of bars makes my wince (accident waiting to happen!) I bought a 1000Nm one off eBay £80. Saved 10 times that by doing them all myself.
You need;
Big torque...
I'd jack it up and check the brakes aren't binding and give the wheel a "rock" to see if there's any play in the hub.
Might not help- but simple and free!