Orpheus, from your "high end emporium" statement I may conclude that
1. there are speakers that would throw 3d soundstage even with mid-fi Rotel.
2. there are alternate amps to ARC that would not compromise 3d sound stage of the same speakers you've described and so possible to say that there are number of alternatives (given quite substantial price range of OP) that would make to sound his new speakers great.
3. synergy is more important than particular brand of amp or speakers.
1. there are speakers that would throw 3d soundstage even with mid-fi Rotel.
2. there are alternate amps to ARC that would not compromise 3d sound stage of the same speakers you've described and so possible to say that there are number of alternatives (given quite substantial price range of OP) that would make to sound his new speakers great.
3. synergy is more important than particular brand of amp or speakers.