if you do have solids buildup on your roots, your plants will start to suffer from "root rot"..suffocating them slowly
but if your roots are nice and white, then whatever works for you!

the real "ratio" to worry about is the amount of feed to surface area where bacteria will be growing..
it hasn't been proven commercially by anyone using aquaponics where you have actual solid waste.. (i've yet to see a "successful" commercial ap system - when i say commercial ap, i mean supporting a business with just sales of veggies and/or fish, without having to offer training courses or "kits" or other sales to support the business)

on the other hand, i've seen numerous ap dwc (or dwr as you call it), fail because they did not take into account removal solid waste

it works in hydroponics when all the nutrients are in solution...and you aren't counting on the ammonia to be converted to nitrites, then to nitrates by bio-activity