In general, it does not make sense to appeal for something like that.
Whether an appeal is likely to succeed depends on the specifics of your situation and it's not a good idea to discuss all this on this site. You would need help from a Greek legal professional (which is presumably neither cheap nor easy to get from Abu Dhabi) to get an informed opinion about this.
But even if you have solid grounds for an appeal, it can take a (very) long time and it's impossible to do without knowing the local language and legal system (that's always true but the letter you received even states as much in the last paragraph). Additionally, the letter also suggests that lodging an appeal by post without formally hiring a lawyer is simply not possible in Greece (it is in other Schengen countries), which makes any appeal more expensive than a fresh application, even if you know Greek and feel confident drafting it yourself.
So in practice you are not going to quickly get satisfaction and save your trip that way. You will only receive an answer several months from now, long after your bookings have expired and your holidays are over. At this point, there won't even be a valid premise for your application (it makes no sense to issue a visa for a trip supposed to take place in the past…) An appeal only really makes sense if you have strong legal arguments and no hope to succeed in another application (and of course for long-stay visas but that's another thing entirely).
Alternatively, you could still lodge a fresh application. Even taking the fees, documents, etc. into account it would still be much cheaper than an appeal and definitely quicker. But only do that if you think there is something you could add to make your case stronger (detailed itinerary, bookings, etc.) without making you look unreliable (don't make up a story), otherwise you risk getting a new refusal and damaging your credibility for the future.