The way I see it, the potential problem with Patricians driving down Cent is not a new class of problem.
As it stands, Yeomen can take Black Soil actions or the like for a good 6 EE per action. If they spend their policies on Expansion instead of Forestry, they can get that EE total up even higher. They only ways to burn EE rely on overflowing Econ or having Econ to spend on planting crops, which means that unless someone is regularly taking Expand Economy actions, we can't do anything about the Yeomen. So, unless we personally dedicate energy to aggressively Expanding Economy, we can't combat the Yeomen as they kill more and more of our cities.
As it stands, Priests can take Build Temple actions to get as much as a full point of RA per secondary action. We have no way to lower RA, and trying to combat this by raising RA tolerance is much too slow.
As it stands, Guilds can significantly worsen the tech crunch by building Ironwork after Ironwork. A couple of lvl1 Ironworks and the Expand Economy action will be basically unusable.
As it stands, Urban Poor can screw us by building more and higher level Block Housing. Since more of those give them more actions, it would be rather easy for the Urban Poor to make us face unsustainable expenses to ensure proper hygiene. At least this one is a problem that solves itself; if the UP are too short-cited to properly build health infrastructure, they will be the first to die in the resulting plague.
Point is, a lot of our factions can screw us, and do so in ways that we might not be able to contest, counter, or reverse. The DL option for Patricians is no different.