Salt, fresh cracked black pepper.... that's all you need... if you feel that your steaks are missing something then it's probably the steak or the cook that is missing. Buy quality steaks, cook them properly, you will be amazed.
I do a reverse sear on thicker cuts, but on anything 1" and thinner a reverse sear doesn't gain you much unless you're cooking on a preheated cast-iron skillet or a dedicated sear burner/sear spot on a grill. Most grills don't get hot enough to do a real sear. For thick cuts (like my 1.75" filets) I go low & slow (225) until the meat hits about 115, then crank the heat and sear both sides to get the browning. Everything in the middle is wonderfully med-rare and the outside is nicely browned. For my normal steaks (1.25" thick) by the time I get the outside browned the inside is a perfect med-rare so I just go straight to the sear stage.
As said, salt quite a while beforehand. This does some wonderful chemical changes at the surface of the meat.
What not to do: Don't listen to anybody that tells you a steak should only be turned one time while grilling. That is pure BS, turn the steak all you like. When I'm searing I turn every 30 seconds or so to ensure I'm getting perfect browning without charring.