My point is: you don't need a large balance on a node to be able to make many transactions, as long as you have transactions in both directions.

Yes. It may not have been the best example indeed. Here's another one: I think a node with 1 BTC in LN can process 10 BTC per day in transactions (given the right circumstances). At 0.25% fee that would earn 25 mBTC fees per day. Seeing this numbers makes me think it's not very likely to happen any time soon though, 0.25% is very high, for my last transaction I paid about 0.01% in fee. And that fee is for all nodes involved in the route.
If you can earn 1 mBTC by transfaring 10 BTC per day though a node that holds 1 BTC, it's still a pretty good profit.