Im also interested, seems a cool project and active community!
I downloaded the wallet but I didnt managed to finish to sync as I have a bit of a slow connection
do I have to download the entire blockchain? how big is that?
I had to do exactly the same, this is the only downside to it. Unfortunately you do have to download the whole blockchain but DeepOnion is not the only wallet that requires this.
You could always try a paper wallet I suppose.