I think generally there is a ton of synergy from amps and preamps from the same brand. For sources, not so much. So I think you can have decent success from just doing the preamp/amp from the same brand but going elsewhere for the source.
Benefits of brand synergy
How important is brand synergy in matching components? This not only includes amps and preamps but also digital sources from a particular brand, say Arcam or Kell. Is this "synergy" important just for impedance purposes or is there an additional sonic benefit of having everything matching? Thanks.