The Eheim nozzle pictured above constricts and speeds flow from the outlet. It directs a fast-moving, narrowly-focused jet of water which, as you say, will not cause much surface movement. A constant jet with one focal point might have some unexpected consequences.
The concept of the ADA Lily Pipe which flares out like an arum lily, rather than constricts inward to a narrow nozzle, produces a much gentler flow which also does not cause much surface movement.
If you use the standard 1/2 or 5/8 Eheim outlet you will find it produces a fairly focused but gentle flow. I use and prefer this form and think of it as the 'cheap form' Lily Pipe - rather than spraybars.
I attached some 1/2" vinyl tube to the outlet of an Aquaclear 402 Powerhead. This is then connected to some 1/2" drip sprinkler tube. The final outlets are made from a compression T and a compression elbow made for the drip tubing.
I've got a Quickfilter attached to the powerhead as my mechanical filtration for this tank. The heater is right next to the powerhead so it will circulate the warmed water to the bottom of the opposite side of the tank.
You can see one of the outlets at the lower right of this picture. The other one is hidden by the rock in the front corner. It's been up and running since I set the tank up on Friday (check out my sig link for a journal of the 20H tank setup). Still letting the tank settle before I start adding fish so I can't give any performance reports yet.