To me the upgrades could be how we edit & work with the Fractal, not so much in terms of tone.Yeah the tone can only go so far, although many of us base our opinion on the axe fx as it compares to tune amps. Once you reach tube tone, that journey is complete. Can Fractal go beyond tube and create something greater? Have they already done this? I dont think we will have much need for a new unit unless it just upgrades things like storage space dramatically, lowers CPU like to where we could use EVERY block and not overload the Axe. Maybe an axe with a built in, super clean power amp? There are a lot of things tjey COULD do, but as far as a preamp goes, we are reaching a majot plateau, I think.