myopenledger
Even if you have only one signer, using option 2 removes the burden of figuring out encryption & secrets management, and makes it possible for users of every compatible wallets to use your application right away (for example see Equilibre.io).
On the other hand, users have to own an account in such a wallet. Hopefully, at some point, every main wallet will be compatible & able to access a wide range of applications.
On the other hand, you could use option 1 with several signers, but it'd require each signer to create a dedicated account in your app, which may be a limitation in terms of user acquiring.
I personally believe that delegated signing is a better solution in almost all cases, especially considering the gain in term of development time, but of course I'm not neutral on that one 🙂