The Classic and V series are very special amplifiers. The VS55 would be a sideway move. VS55 suffers from the same low power and they can both sound somewhat closed in at times. If it were me I would just look for a Classic 60 or maybe V70 to get a little more power. The V70 is very similar to the Classic 60 except that it is balanced. some of the later CL60 amps are also balanced.
I have not heard a VS115 so I don't know how it compares. But that might also be an option. Much easier to bias than either the Classic or V series amps.
I have owned both a Classic 60 and V70 as well as a VT100 mk3. And I have listen to a lot more. I owned the V70 for many years and finally sold it after I bought my Ref 110. Though more detailed, I never thought the VT100 mk3 was truly better than the V70. The Ref 110 is the first ARC amp I thought was significantly better.