Chance me threads are always difficult. The overall acceptance rate last year was about 20% with record # of apps. Of course, OOS acceptance rate will be lower than that 20% #, maybe 3-4% below that based on prior years.
There are roughly 1,400 Engineering “seats” +/- in the typical Michigan freshman class of about 7,000 +/- enrollees. By comparison, LSA has about 4,400 “seats.” At least 1/2 those CoE seats likely go to in-state students.
Having said all that, the CDS for UMich changed this past cycle. Test scores are considered “important” now, instead of the prior “very important.” The two most important factors are GPA and course rigor, which your child seems to have. Obviously, the test score improves your kid’s app.
The essays were always “important” as a factor, but now they’re just as important as test scores. So, I think the essays and LOR will be critical to an EA acceptance. Otherwise, deferral/postponement and then I’d say good possibility of acceptance in one of the RD/postponement cycles.
What helps even more IMO is if your kid’s HS has a good track record of yield to UMich.