I don't see how the unit can be shrunk down below an FM3 and still be effective as a modeler that'd fit into the product line.
"The entire product line was conceived years ago. The goal was to maximize the number of parts shared between products. The footswitch PC boards do three switches each. An FM3 has one board. An FC6 has two. An FM9 has three and an FC12 has four. All products use the same LCDs, encoders, side plates, etc., etc. This reduces cost and repair inventory. The FC6 and the FM3 are basically the same enclosure. The FC12 and FM9 are basically the same enclosure. This isn't a huge market. Margins are thin so you have to think of ways to minimize development and product costs. Parts bin methodology is the route we took on this generation."
[1]
The FM3 by itself is a nice trade-off of size, power, capabilities and portability, and it's expandable if we need more switches and it fits into their design goals by reusing components.
Sticking with that methodology, the unit you propose would still have three switches and the same display in the same size chassis and most likely the same processor, the only thing it wouldn't have would be a firmware that contained the same depth when wanting to adjust things. But that's already in effect because, for example, we have the "Tone" screen for Amps, which has the same controls as the original amps, or the "Cab" screen for Cab blocks and IRs. Several years ago Fractal created the "simple" interfaces as the first one for each block type to help people move up the learning curve, recognizing that not everyone wants to see all the features all the time.
The manual for each of the units has this statement in the FAQ section:
Fractal isn't about dumbing down the interface or reducing the unit's abilities to the point that it's unable to be recognized as being a Fractal unit, they design professional gear made to be used in professional situations. Sure, we have a learning curve, but I'd much rather have that and grow to use its capabilities, than have something that can't do what I want a year after purchasing it.
Other companies target a different type of user and that's fine. Fractal doesn't seem to be interested in that same demographic and that's fine too.