I wouldn't have thought it would present too many problems for RANBI departures etc. If you're using 30, the departing traffic would be pretty well clear of a SHJ hold by the time it reached 6000'. (Perhaps they'd have to maintain 6000' until 15 miles?)
If 12 was in use, departing traffic would have to limit their climb to 6000' until clear of the holding area or alternatively, they could simply re-route the RANBI departure slightly north of its current track. A right hand hold would have the arriving traffic holding in the airspace between DXB and SHJ, so it shouldn't mean much of a re-routing for departing traffic.
As for the jumble of paints in a hold, the Heathrow controllers seem to have that problem pegged.
I'd be willing to write to the company again suggesting they approach AUH asking for a different, more fuel eficient, system, but I'd like to hear some ideas from the ATCOs who man the 'coal face' first, as it woud be a waste of time suggesting something you people can see won't work.