I agree with all the comments above. You will find that one visit won't be enough and you'll want to return to Aruba again and again due to the fantastic weather. With regards to safety, the island is very safe and an absolutely wonderful place to visit. Over the past few years, there has been a lot of construction on the island. Due to this, there are a lot of workers on the island from neighboring countries....and this has correlated with an increase in occurrence of petty theft. So just be mindful to always lock your car when you are at the beach or parked at your hotel/villa to keep your valuables secure. Also be sure not to leave any valuables in your bags on the beach, just as a precaution.
Right now for example you can only book flights through June 30, 2015. The only time I would buy airfare that far in advance would be if it were a peak period such as Christmas or New Years or if it were a bargain. Right now Delta has fall flights from Atlanta to Aruba for as low as $323 which I have never seen before.