Since this is a scenery density generation over a given area issue, dialing back on the outer ring's 50 value will have the biggest effect in reducing the total object count. What you will notice is that the farthest distance that you can see objects will be reduced, so at some point you will be back to noticing them suddenly appear in the distance. You will still get the benefit of not seeing extra objects popping up at the intermediate ring distances as long as the densities are still all the same.

p.s. AnKor discovered that the game will look at all of the lower budget levels for missing ring values if you skip over any. In my example for Level Five, I had to also edit the lower levels (1-4) to eliminate the larger PatchWorldDim entries.