Pin levellers are no good on a floor that is massively out and IMO are only good for latexing floors that are already flat and are having vinyl laid. As above, trowel and spiked roller for me
Getting rid of air bubbles is vital for soft flooring, but the benefits of a spiked roller in relation to tiling for me are that it removes any ridges that might be left with certain levelling compounds and just helps to level things out that extra small bit, and it's that extra small effort that makes all the difference in our trade