If you drilled to the side of the top (I wish I had) than you maximize the room. I also recommend a second large hole for water pouring and pH/PPM testing. You could cover that with another pot. You could still fit several pots on top. Consequences are limiting max light height, and they tend to get bigger in hydro, could shade out a neighbor under the those conditions.
Under normal DWC, the splash of the bubbles and other splashing you can make, hits up the sides of the netpots. The level is kept under the pot to facilitate this maximization of oxygen. In a bucket, you will have to water the soil, but a drip is fine.