He would have trouble getting on the floor at the top tier D2 programs such as Augustana that won the National Title last year and actually won at Carver. Those top tier D2 programs are actually better than those bottom dweller D1 programs. So yeah, he probably could play for Drake and Montana State and Quinnipac but I just dont think he is talented enough to play in a major D1 conference.
I've personally attended about a dozen Augustana games over the past 3 years and IMO Ellingson would be a major contributor if not an instant starter at Augie (as well as any of the teams I watched them play) from game #1. He would have no trouble getting on the floor.
As a point of reference consider former Iowa player Brandon Stubbs who transferred to Augustana before the 2012-13 season. Before he backed out, Billeter said that Stubbs would play a major role for Augie right away. Augustana finished 21-9, ranked, and advanced to the 3nd round of the DII tournament that season.
To maintain your "Ellingson is a DII player" claim you would have to also believe that Fran McCaffery was completely fooled when evaluating Ellingson during the recruiting process and that his decision to offer Brady a full scholarship was a monumental error. So far, the facts don't back that up.
Ellingson has made 46.4% of his FGAs against DI opponents while at Iowa. Certainly not a phenomenal shooting stat but not terrible either. In addition, a few of his better shooting performances last year were against quality D1 competition:
3-5 all 3s, 9pts vs. Dayton
2-2, 1-1 3PT FGs, 5pts vs. Wichita State
3-5, 2-4 3PT FGs, 8pts vs. Purdue
His best scoring game so far was against Coppin State (7-8 FGs, 1-2 PT FG, 5-6 FT, 20pts) .... a DI team which is above Brady's talent level if you are to be believed.
I'm not trying to make the case that Brady Ellingson is an All-B10 player or even a Top 40 shooting guard, only that he is a legit DI player. I have already posted my belief that he is capable of contributing 6 or more ppg this year. BE needs to show he can play better defense to get major minutes but Fran will look for him to be a 3PT threat when he is on the court.