The upgrade was the installation of new FD processing and radar equipment. Someone who works there will have to let you know how it's going.
I'll give you the Area perspective on diversions (as you are probably talking to us anyway). You don't get any priority when diverting. Why should you? If you are saying you will be short of the minimum requirements if you don't get direct tracking etc. the moment you elect to divert, then I'd suggest that you are leaving your divert until too late. Why should you get priority over anyone else? Leaving your divert until you require direct tracking and planned level or else become fuel critical, is setting yourself up for "the big E call". It may not be physically possible to give you your requested level if there are lots holding in tight airspace, such as around DXB, during a diversion. If you put yourself in an emergency situation, then you should be suspended/investigated. If you have followed your company's rules, what's the problem (deep breaths...)?
The big E call may solve your (ATC) problems
Quite the opposite. "The big E call" makes our workload go thru the roof, and generates said paperwork/investigations etc at our end, as well. It does mean you will get exactly what you want, but questions will be asked (and rightfully so). For instance, the guy who was holding in the stack below you, and elected to divert 5 minutes before you so as not to put himself in the position of having a fuel emergency, now gets pulled off the approach/vectored out of the way/held again etc etc, just to let you straight thru. Why should someone who doesn't put themself in an "emergency situation" be penalised?
It's the same with arriving on frequency "fuel critical". Why should everyone else (who has carried enough fuel) be penalised, unless you declare an emergency? I understand the reluctance to declare emergencies, but unless you do declare, you won't get anything special.
It will lead to an investigation involving company and the authorities,
Rightly so. Wouldn't you want your company investigated if their fuel or divert policy was creating undue risk?
In answer to your question
So, is a diversion just another flight for you ATC guys?
Yes and no. It creates a lot of work, but in terms of priority, yes.