The Navis is a great option when it comes out. For now, given your sources, I'd recommend two items on audiogon: the project prebox2 dac and the exposure 2010s2 integreated with the silverlines. That would be a noticeable step up from the kefs and about the same price as an nadc368 and added mdc bluos module while even better performing.
Elac is great though: the Navis is a great choice as is the upcoming elac ddp2 to drive it, the ddp2/dpa2/ppa2 with any great monitor speaker (studio electric m4, dynaudionspecial 40, silverline minuet grand) is also a smart and flexible system!
Any of these choices would get you into a leagye if sonic reproduction above the ls50s and open up paths beyond redundant digital conversions.
Elac is great though: the Navis is a great choice as is the upcoming elac ddp2 to drive it, the ddp2/dpa2/ppa2 with any great monitor speaker (studio electric m4, dynaudionspecial 40, silverline minuet grand) is also a smart and flexible system!
Any of these choices would get you into a leagye if sonic reproduction above the ls50s and open up paths beyond redundant digital conversions.