What have other units done to showcase a memorial for their fallen soldiers?

Usually a framed photo of each with a bio arranged in chronological order of those lost. I've seen them with a bio that includes the circumstances of death. This is what was in each BDE level HQ I've served at. It is common to see one representative helmet, boots, ID Tags and de-mil rifle display next to the memorial wall. In the high school I teach at, we have a memorial to two of our graduates who were KIA in Iraq and Afghanistan. They have a nice photo, bio, and a shadow box of their decorations for each.

You have to make it sustainable. People get emotionally invested in these unit level memorials. Family members get irate if their soldier was somehow overlooked. Your unit command needs to come up with a criteria to make it on the wall. Is it KIA? Is it killed or died on deployment (DNBI)? How will your unit handle suicides? What about those who died while training? Recommend you have a written criteria (SOP for the memorial) and have someone else like the BN XO and CJA (ethical advisor) review it. What is the funding stream to handle it? Will you be able to sustain that?

The Battalion that I belonged to has 2 headstones on veterans row at the local cemetery that has members on that have passed away.

My unit had a memorial wall in Europe for unit soldiers killed since 1945 during the Cold War. They added an additional name on year-dated plates every year. We added a plate for every 4 of the calendar years I served in the unit.
This is a little off-subject for what you want but for examples; see how the Patton Museum has unit memorials. I can't name them all but Monuments at the park include:
Tank Destroyer Forces
World War I Tank Corps
5 Cavalry and Armor Regiments
16 Armor Divisions with 1811 Battalions
23 separate Armor Battalions