Better to level before seeding, then the problem is solved

I see the logic with this, though I'm not sure I have the time to do a good job leveling.

Assuming I CAN NOT level, how should I proceed?

Assuming I CAN level properly, is the overseeder the preferred machine?

Is the lawn big? I have .25 acre and I just spread seed by hand. It needs to be leveled though. One decent rain before germination and those spaces between bumps will become water highways and push the seed to where ever excess water runs off.

I had the same issue under one of my trees in my backyard. I threw fescue seed under the tree in the spring. The leaves had not fully formed on the tree yet, so there was good sunlight to get germination and growth started. A 30% chance of rain later in the week turned into a thunderstorm. I had an awesome, thick patch of fescue 10 feet away where the water runs. I should have placed a thin layer of soil over the seed.

4 weeks ago I did the same thing, but this time there were leaves on the tree, so not the best growing conditions. No rain in the forecast. Threw seed. No dirt again (risky). Watered by sprinkler. Dense fescue under the tree.

I have approximately 1200 sqft of lawn. Broadcasting the seed should be straight forward. I'm just trying to figure out the best way to prepare to soil. My understanding is that you get better results if you can scuff up the soil.