I don't think ebay would get involved in anything like that as they are a worldwide website and there must be thousands of different courier companies their sellers can choose from.

I have no doubt you had a horrendous experience with aramex and it sounds as if  7,000 other people were annoyed enough to leave a review too but the thing is, for every one of them, there are probably many others who received their items as expected and the recipients never even thought of leaving a (positive) review.

We tend to take it for granted that we'll get the service we paid for and mainly notice if things go wrong.

I think daydreams is correct, your best bet, if you find aramex isn't good in your area(and it could well differ from area to area), is to check with sellers prior to buying