Some people won't agree, but Dubai is an amazing city. I was there in January 2016, it was comfortable then. Ironically, our flight was delayed inbound due to heavy rain, they had to shut the airport
.
There's absolutely tonnes to do in Dubai, as the one said, there's also ski dubai, go dune bashing, legoland dubai has recently opened iirc, make sure you visit the creek and Deira for the gold too.
You will spend a full day in Dubai mall, although the electronic stores are all on the 4th floor if i remember correctly, it's pretty much a full floor of shops like currys lol. Things are a little cheaper but not worth it imo. For example, i was looking for a new laptop at the time, but they all had arabic on the keys as you'd expect. That will have issues if you wish to sell on in the future. If supercars are your thing, there will be loads outside dubai mall.
Taxis are dirt cheap too, we travelled everywhere by taxi, even back to the airport. We got a taxi from our hotel on Shiek Zayed road all the way to an outlet mall near the desert, it was about 30km, and it cost us £10.
You are correct also that they do use the same plugs as us so no need for an adapter.
You will have a great time, though i don't envy you going this time of year, it'll be so hot!