This is very similar to the upper-lower margin + dividend model introduced in Backfeed: http://backfeed.cc/assets/docs/BackfeedEconomicModel.pdf (and earlier in La’Zooz). Where there the floor (lower-margin) value was reflecting full-reserve scheme, Bancor (https://bancor.network/whitepaper/en) recently suggested a (fixed) fractional-reserve scheme. Clearly, you can play around it and have any sort of dynamical-reserve scheme you want. Regarding the “beneficiaries”, or the dividend scheme, as well, you can play with all sort of schemes. Lastly, the interesting part is the protocol for determination of the ceiling (upper-margin) value: it can be a result of on-going vote of some reputation system; or, it can also be algorithmically designed in relation to the density of demmand and supply (as in the Bancor protocol and some earlier versions of a similar protocol in La’Zooz). The bottom-line lesson there, is that there’s no single scheme that is “better” or “right”, but you can play around with infinitely various schemes with various pros and cons. Overall I totally agree that this general idea creates a more stable economy (in fact, that was my original purpose of introducing it back in La’Zooz, to create a stable cryptocurrency), and on the other side, some people like it less due to its market intervention (which, to me it not ncessary a problem).