With ARC you have to be careful. Their sound, from piece to piece, is not that consistent. Overall, they do make some great equipment. For comparison, I put my VT100 next to 2 other amps I had at the time; a Rowland 112 and a VAC 30/30. Both had a sound that was noticeably on the darker side compared with the VT100. While that's just a matter of personal taste, something else I can tell you about the 2 is that they were both cleaner and more pure sounding. In the high frequencies, the ARC had a bit of noise or electronic haze to it. To be fair, it wasn't too prevalent unless compared directly to the other 2 amps.
All this is leading up to 1 thing. You really have to find a way to listen to any new gear with what you already have. Its possible that ARC may work very well for you. If I'm not mistaken, your speakers have soft tweeters. Mine don't, and I'm very sensitive to high frequencies. The Verity may be forgiving just in the right place that an ARC piece will benefit from.
Another thing you will probably need to consider is feedback. Your BAT doesn't use any global neg fb. That's part of the reason why it has that dark, pure sound. I know you are looking to get away from that, but if you choose something that uses feedback, I would recommend a really thorough demo, because there will most likely be some trade offs.
Personally, I think your BAT is an excellent piece. If I needed an integrated amp, I wouldn't hesitate to by one myself. Thats why I asked about your source. Both your amp and speakers have enough resolution to easily pick up on any changes you make to your source. That might be something worth looking into. Also, I don't know if you would ever consider separates, but my current system consists of an Aesthetix preamp and a pair of Ayre V-5's. Given your descriptions, you would probably like the combination very much. For your speakers, just 1 amp would probably be more than enough. The combo is much more neutral sounding while still using 0 feedback.
