I think that is where the money lies, with live out allowance/provident fund etc. Earning that extra bit is easy. I have seen the pay slip. It's more for a FO in Dubai than one of the returning Abu Dhabi pilots who dropped all seniority.
Yes. The provident fund is the biggest difference in my opinion. I would prefer living in Abu Dhabi now than Dubai. Your costs are higher in Dubai also just to factor that in. Also your friend might be on the SFO salary which would be higher. Then again once Riyadh start recruiting for their A321 fleet next year, not many major airlines in the region with A320 captains and FOs with expats so that might make a difference.