Abu Dhabi is much improved but still leave a lot to be desired if you get caught in security between the two terminals.
On the whole I have found Etihad punctuality to be no better or worse than others and as long as you have booked on one ticket I would not worry about connections. bad weather can occur anywhere and then it simply boils down to how well they deal with it - I was lucky as was 4 hours late once due to fog closing the airport but my connection had also been delayed by the same fog.
As far as traveling in economy then I would not worry about the airport