I know that there is a NG+ Category, but im curious as to why there is no normal 100% category as you cannot collect collectibles again. My thoughts for that category would be:

-All Main Cases

-All Villain Cases (Harley Quinn, Clayface, Mr. Freeze)

-All Collectibles (Batarangs, Historia Strigidae Pages, Street Art, Landmarks)

-All Side Activities (Fast Travel Points, Audio Recordings (from caches), Secret Identity Information Planted, batcycles time trials, and all training area exercises finsihed.

-Level 30 (no need for a ng+)

Of course, some of the side activites reset upon ng+, hence why the level 30 is the required level. This way a 100% could be completed only in normal NG