I think the biggest difference is that xrp/xlm are more focused towards payment systems. Hydro seems to be more focused on finance as a whole.
It does seem like they might be targeting the same kinds of companies as Hydro though
In terms of general design, the main differentiator is the hybrid private-public model Hydro promotes. It adds blockchain as a separate layer to off-chain systems and integrates the two, so companies don't need to rebuild their systems from the ground up with blockchain (and waste tons of money and time). This is how we think blockchain will get adopted in the real world more readily.
So it seems like then hydro might be targeting a different demographic than the other two since they require more of a completely restructuring of any application currently used right? Are there any other tokens focused more in this area like hydro is?
Brings up an interesting thought about IBM - they are building apps with Stellar but also one of the main funders of Hyperledger