You have a pretty detailed amp and very resolving speakers (Merlins?) I believe also.
Unless ultimate detail and resolution is your thing, ARC may not be the way to go in your case.
I think you are on a good track. I would love tohear the resulting system no matter which way you go with the pre.
Not sure if you do phono or not, but be sure to take that into account in that some pre-amps have this built in and some not and typically it will add cost.
