I too was drooling at the Mavic Air since it was launched close to the time I bought the Spark. However in my case I have been extremely happy with the Spark and am glad I did not opt for the Mavic. This is for a few reasons:
1. I am surprised to find that I am using the Spark more for photography than for videos and there is no difference in photo quality between the two. The videos I do take are typically short clips posted to social media so 4K is definitely not needed.
2. I am a new drone pilot and feel much better about learning on and experimenting with the less expensive Spark.
3. Most accessories, especially
batteries are much cheaper for the Spark than for the Mavic.
So far the Spark fits my needs incredibly well and any upgrade would be solely for my ego to say I have the best, there is no additional feature or functionality that I wish I had at this time. I will however likely purchase whatever may eventually replace the Mavic Air, since at that time I will be a much more mature drone pilot/photographer/videographer.