+1 Zesto Leto II although Herron's Reference line stage would be the obvious choice.
You don't describe what you mean by "wasted feature-sets". If by that you mean basically a remote controlled volume and selector switch then all the recommendations so far, including mine, would be invalid.
With that said, I would upgrade your DAC first, You may find that with a very good digital source, you may be satisfied with the line stage or preamp that you currently own.