Let's look at three different approaches to Helix Amp:
Helix Amp 1 has a similar UI cluster to Helix Floor (big screen, knobs, buttons, etc.), the same two DSPs, and presets are fully compatible with Helix Floor/Rack/LT/Native. Works with Helix Control (additional $449). On the downside, it's considered awfully expensive for a solid state amp, and amp customers really don't like the huge color screen on stage. Quite a few customers say "If I'm bringing an amp and Helix Control to a gig why don't I just use Helix Floor with whatever playback system I prefer?"
I guess this is basically Helix "PowerRack" similar to Kemper's equivalent. It would probably have its fans as you don't have an extra rack unit for a poweramp, you have the "officially works great with Helix" poweramp built in and so on. I don't know how many people go for Kemper PowerToaster vs PowerRack but I assume the PowerToaster is more popular just because it doesn't need a rack case.
Helix Amp 2 is like Helix Amp 1 but has a "headless" UI with traditional tonestack knobs—no screen. It looks and acts much more like a traditional amp but the only way to edit anything beyond tonestacks and channel selection is to hook up HX Edit (or Pedal Edit from Helix Control). Quite a few customers ask "What happens in X years when Line 6 no longer supports HX Edit? I can use my Marshall for decades with no worry!"
This probably depends on whether MIDI control can expand the control options or how small the Helix Amp 2 is by throwing out the Helix Rack UI.
I am not at all worried about computer editors - mobile apps are far more likely to be problematic over time as they become incompatible with the latest forced update iOS or Android. Or they get delisted out of app stores so you have to hunt down some .apk file from dubious sources.
Helix Amp 3 looks somewhat like Helix Amp 2 (also no screen) but adds a few extra knobs and buttons to access its limited number of simultaneous effects. It doesn't have the full signal path or block compliment of Helix Floor/Rack/LT, Helix Amp 1, or Helix Amp 2. You can tweak most of what you want from the front panel, but at least it looks like a real amp. Helix Amp 3 presets can be loaded into Helix, but not the other way around. Quite a few customers say "Well, this isn't really a Helix Amp, now then, is it? You shoulda' called it Catalyst XL or something."
This would be my personal favorite. I find that I am pretty ok with things like fixed signal paths, or limited options when well executed. My pedalboard is pretty much set the way it is and I never have the urge to change it around.
It is definitely a bit like a "Catalyst XL" for sure. But as I said earlier, the Catalyst fx section was poorly executed, making it limited and inconvenient without using the editor.
For immediate fx control I'd probably want something like this as a baseline set of controls:
- Boost/overdrive: gain/tone/level
- Compressor: compression ratio/level (I'm a simple guy when it comes to compression!)
- Modulation: depth/rate/mix/pre-or-post
- Delay: time/feedback/tone/mix
- Reverb: pre-delay/decay/tone/mix
Let's say these are encoders with LED rings for value, then we could get by with a model selector knob, 4 param knobs, and 6 push buttons for which of the 5 fx types you are editing + bypass toggle button.
Sounds a whole lot like the BluGuitar Amp X at this point, right? I expect that device's biggest blunder will be not using infinite rotaries for fx parameter control, requiring you to do the "wiggle until you hit the saved value" dance familiar from pedals with presets.
IMO, any of these might set the interwebz ablaze for a week or two but none of them feel like anything that would actually sell, especially long term. Prove me wrong.
This would heavily depend on how they look (looks are important!), how much they cost and whether they fit into that sweet spot where they make sense to people who are otherwise overwhelmed by the options in a Helix, or who want something that is better than a Katana or Catalyst, but not dumbed down like the Fender Tone Master amps.
Helix Amp 1 would be probably the weakest option. A bit of a "why didn't you do this X years ago?!"
Helix Amp 2 is either hated by the "no apps" folks, or people accept that it compromises to be smaller and more portable.
Helix Amp 3 might have the most support just because at this point Line6 has a reputation for good amp/cab modeling and fx. There's other amp + fx type amps on the market from H&K, ENGL, Diezel etc but often the fx can be a bit "eh, it's fine" level stuff rather than truly competing with the best pedals like Line6 fx do.