I wrote an answer to a similar question a few days back, which covered two technical aspects in which Stratis has an advantage over ETH, in particular. These are both just opinion and I'm sure there are good arguments against. You can see the post here (I won't quote the whole thing because it is pretty long, you can just click through to see it):.
Moving away from the architectural advantages, another advantage would be the dedicated Stratis Consultancy. Development of decentralised-peer-to-peer-network-based applications is really tricky, and very dangerous given that you are dealing with code which is literally people's money, and isn't just code which exists on top of some infrastructure to insulate it from people's actual money. The Stratis team are made up of experts in their industry. The Stratis Consultancy is in the business of selling that expertise. Clients that engage with the consultancy, and thus build on top of the platform, are better placed to successfully build their applications than those that don't.