Better modules to upgrade the Bel Canto S300i

I would like to know if there are better, newer, more powerful modules that could be dropped into the Bel Canto S300i without significant modifications.  I'd like to have a Bel Canto integrated and all the newer ones/receivers are even less powerful.  I like the form and appearance and would like to match the Bel Canto DAC and transport I already have.  Thanks