I did some more sheet stuff. I combined dodge/parry on various rating levels ranging from 10 to 40k rating.
Example. If you look at the 30k rating graphic.
At 0 rating you will have a dodge/parry ratio of 1:0.
At 30k rating you have a dodge/parry ratio of 0:1.
To conclude it. In most cases you will live in a world around 15-30k stength and probably about 10-30k rating. If you even out your dodge/parry ratings you will most likely notice nearly no avoidance loss. So as long as you keep your dodge/parry rating even you should be fine.
If you go all out on one side you will see a difference though. Thus if you have 20k rating to spare spend 10k in dodge and 10k in parry rating and it should be ok.
It's actually pretty nice since strength and rating scales with gear. Thus your strength and your rating grow evenly and keep everything in line.