You can't really "predict" the bass quality of a headphone. You can look at reported measurements and specs, then perhaps make a reasoned judgment whether the bass will be sufficient to your tastes. There is no replacement for listening, however.
Basically, the bass quality is dependent on the physics of producing sound. You have some sort of driver that is powered to produce sound from a given signal. How that driver is designed, powered, and the signal it's fed, all determine the type of sound that results.
Some of what you are describing and asking about include the concepts of frequency response, sound pressure levels, and transient response. All things being equal with a dynamic driver, a greater excursion means a higher sound pressure level. Like all things in the physical world, there is a balancing act: a lot of excursion may require a lot of power and the material may have a greater chance of deforming and causing distortion. You can minimize the excursion with a larger diameter driver, but then that, too, becomes more difficult to maintain the exact shape while in motion. You can re-design the driver type to provide more sound pressure with less power and excursion (like the HD800), or you can re-design the driver so that large excursions are ridiculously easy and there is less chance of deformation with large excursions (like the Focal Utopia). Both can result in great bass.
The rest of your description seems to question the difference between sound pressure level of a driver versus the transient response. Some of this is amplifier-dependent, too, but transient response can be thought of as the driver quickness, while sound pressure response can be though of as power and frequency response, or the sensitivity at a given frequency. Both are needed to provide deep and tight bass.
The HD800 is one of the easiest headphones to equalize for greater bass. The capability is still there, but the bass response is a little subdued in its non-equalized response. However, the bass is very quick and there is no lack of extension (the HD800 is better in this than the HD800s, IMHO). The outstanding performance is a direct result of the proprietary ring-radiator driver design that Sennheiser invented. Sennheiser continued to use coils that resulted in 300 ohm impedance in the HD800, though, so you need an amplifier that can swing more voltage than current.
As for the Focal, it depends on the excursion of the driver to produce great bass. In their case, the driver design is such that tremendous excursion is possible with very little power. However, that also means that inherent damping is very, very low. This means you need an amplifier with a superior damping factor at the Utopia's impedance to properly control all that excursion. Most any amplification can push the driver out, but it takes a great damping factor to pull it back in. I haven't seen it myself, but Focal owners have described that you can see the drivers swing back and forth simply from moving the headphone in the air. At the same time, there are isolated reports of the drivers bottoming out in the cans, too. All that adds up to a very quick, highly detailed headphone driver, but it must have a quality amplifier at a much lower impedance than the Focal headphone.
Bottom line, you are going to always have the potential for great, high-quality bass with one of the flagship headphones. However, you also need to include the correct amplification in your requirements.