I think the question is perhaps a little "flawed" - no disrespect intended - due to the implicit assumption that "quantum" is related to size. Mostly, smaller scales are where quantum effects are more "significant"
A single photon being absorbed by an electron of an atom in a molecule of air will go utterly unnoticed and will not change the ensemble perception of the state of a room in a manner that makes any real difference to anything that human-scale interactivity requires.
Yet when considering the scale of the atom, that photon has changed entirely the energy of the atom system as a whole, the electrons will reconfigure and may even cause changes to the chemistry in terms of its related energy dynamics within the molecule
So in this regard, it's forgiven that there is notion of a "quantum scale" - this is further not helped with a lot of Pop science actually using that very phrase in this way.
Yet the 'reality' (for want of better word) is that the principles of quantum mechanics apply everywhere at all scales - and the extreme example is that of Black Holes whose event horizons can be immense.
________I know what the OP meant, but I wanted to clarify that "quantum" is not something confined to a particular scale range-
So with regards to "will there be a level of detail revealed that delves smaller than current?"
Well physicists are always trying to find models or structure that can describe in a manner which matches what observation shows - and this has inevitably lead to looking more and more closely (therefore on smaller and smaller scales) - Although in many ways we have reached a particular barrier -
As mentioned, on the small scales, quantum effects become significant. A photon absorbed by an electron can change that entire system dramatically. The more energy the photon has, the more drastic the change.
But we 'use photons' to 'see'. And to "see" at smaller scales, we need higher resolutions which is achieved by using shorter wavelengths* - Shorter wavelength photons carry more energy, though - so not only does this make such an attempt to "see" a system more disruptive to the system, but in producing the required energies takes an amount of energy. An approach to provide this energy is in accelerating nucleons to almost the speed of light and colliding them together which provides a considerable amount of energy and the resulting scatterings represent many potential ways to reorder that energy.
The LHC and its components represent the largest, most powerful such group of experiments and it takes something like 1.5 TW (Terrawatt = 1 000 000 000 000 Watts) energy consumption in a year.**
With these energies, we can 'see' evidence for Quarks and at least sizeable masses of "glueballs".
There's plenty of theoretical descriptions of process and objects on the "really small side", and these are very well formalised mathematically and a good deal of experimental data supports a good deal of the current standard model which reaches limits around things like neutrinos.
At this point, though, the nature of "size" becomes questionable, since the point particle model becomes less practical and gives way to the more accurate predictions and less problematic (with regards to particular contradictions with a point particle scenario at least) of QFT which actually increases the 'size' of the spatial extent of such 'entities' whilst simultaneously stamping out concepts of internal structure, since entities are essentially reduced to a collection of specific statistics.
That's not to say that, for example, an electron might actually be an ensemble of something, but the perception of a little ball with smaller things wiggling around inside is not applicable - in some theories, the wiggling itself, by pattern and timing is what gives rise to the measured properties of the "larger" entity.
In this way, some theoreticians have skipped a whole lot of size scales right down from quarks, electrons and neutrinos down to the very limits of what it might even mean to have length or "size". Whether there will ever be experiments even possible to support this or not is a huge undertaking. To even get anywhere near, you'd need an LHC the size of the solar system...
*
Imagine painting a picture using a decorating paintbrush compared to a fine artist brush - the finer artist brush with its narrower width can provide far greater detail in smaller regions of the canvas.
