Not really. The problem is the CPU load, not GPU, so reducing GPU settings will have little to no effect.
For what it’s worth, London is a notorious resource hog, so you’re not doing horrible getting 30fps there with your current setup. Someone recommended upgrading to the 5800x3d, which is great advice if you can afford it. In the meantime, try reducing your terrain and object LOD’s a bit more, and your AI traffic (including roadway, water, and airport traffic). Those are the biggest CPU hogs in the sim. Don’t worry about your other graphics settings right now.
If you really want to try fine tuning, it wouldn’t be a bad idea to kill any unnecessary background programs. If you use Razer Chroma for RGB control, try switching to Signal RGB. I’ve found Chroma caused a lot of stuttering in the sim even though it doesn’t appear to be CPU heavy, and seen many others report the same.