actually, the only think great about IOTA is zero fee and it was an old coin.
If it survive through the past years, it will develop stronger.
The % of people trust new coin is decreasing, they prefer old coin with developing.
If you don't know then IOTA becomes more stronger and faster as more people start using it. And as its user base is increasing its transaction speed has decreased tremendously. So like you said theres not just one good thing about IOTA but numerous that will make this whole page short if I start typing.