Weird, As far as I know Axon 7 has more power output than both v10 and v20, It has both a good dac and good amp, and for real life test like gsmarena test, while loaded Axon 7 had less crosstalk than both smartphones and same noise floor as the v20, headfiers convinced their selves that lg v series is the best for audio despite having a less impressive amp for a reason, going a step further and comparing it to full sized amp/dac is not logical, that's like saying lg v10 hiss is the best quality, anyways what was your model?? A2017G or A2017U? I am interested of your comment because you made the Axon looks like nothing and the Vs dominate by large margin.
For the price Axon is not a step down, I don't know what you're thinking about but having a front facing stereo speakers, samoled display and UFS 2.0 storage and usb 3.0 speeds that even the v20 doesn't have (atop of having similar premium build hardware to the v20 while being cheaper than both) is a step down from the v10 ?? interesting...
About audio tweaks such as dolby and viper, Just saying I would stay away, they color the sound even when you keep the settings as they are, both have a 6 band eq which is (lulzworthy) to my neutron music player, digital gain distorts audio and other features just color the sound, this comes from a guy who used to have both of these mods.