No I wouldn't because the T&Cs state that you'll receive an upgrade to an Executive room, Club room or Suite. Since you have been upgraded to an Executive room, the hotel has followed the rules and so not too much to complain about.

Of course, it is worth politely asking but I would graciously and immediately accept a negative response.

I find the iPhone app great for checking upgrade status on the day as I am heading to the hotel. Frequently the pre-assigned upgrade is improved on arrival day itself.