Upgrade from Sonus Faber Venere 2.5 to ?

If you like your current setup why not just move up to the Venere 3.0 if you're wanting a little more bottom end and extension? Between your amp and speakers are you sure the amp is the stronger of the two? Depending on your room size a larger speaker might not be the first step. What are the dimensions of your room?

Thanks for the suggestion. My room is 14' x 18', speakers against the 14' wall 8' apart and 8' from the listening position. The amp certainly sounds great. Before the AA Maestro 70 I was driving the SFs with AA Verdi 70 and DK Design VS-1 Ref. MK II (150 @ 8Ohm). The Maestro 70 is much more musical and can drive the SFs beautifully. So, IMHO amp is good. 

I auditioned the PMC Twenty 23 driven with Rega (not sure of the model though) that puts out 140 into 8 Ohm, but was not impressed enough to make the switch. I'm going to audition them in my listening environment next week, but I'd like to get some suggestions from others.

Check out Dynaudio. There are several models in your price range. 

I had the 2.5s in my system for a few weeks on demo.  They are indeed very good speakers for the money and do many things well.  But they of course have their limitations given their price, and I found them, not surprisingly, to be at the lowest lows and highest highs.  The bottom is good for the price/size of the speakers, but they run out of steam quickly down there and as a result lack a bit of punch.  Also, while nicely detailed up top they lacked the last bit of air that helps more clearly define recording venues and the like.  Imaging, while very good, did not quite portray depth and scale that other speakers have achieved in my room. 

All that said, I've not heard the PMC speakers you mention, but given the reviews I'd be very surprised if they don't sound significantly more accomplished in the above areas with your amp and in your room.  As you probably know, they should be aimed straight ahead with no toe-in to achieve proper treble balance.  I'd be very interested in what you find with an in-home demo.  Other speakers I've heard that best the 2.5s in these areas are Joseph Audio, Reference 3A, and Silverline among others.  Hope this helps and best of luck in your search.