I am a Dreams bride but I have been to Moon Palace in the past. Moon Palace is gorgeous but it is a lot further away from not only the airport but the action. With Dreams it is right in the middle of the hotel zone and also a lot of the bars (like Senor Frogs, Pat O'Briens, Hard Rock, etc).
We too were torn because we are at an all inclusive why would we pay extra for a reception but we decided it was the least we could do for our awesome friends and family who are making the trip down to see us. And the cost is nothing like you would expect here.
Plus Dreams is close to other hotels. For example, my aunt has a lot of marriott rewards points so they are going to stay at the nearby marriott and then on the day of our wedding just pay the $50 day pass to come to Dreams.