maries1120 - despite the name, Mountain Ash is not a true Ash (Fraxinus), it is a Sorbus, so EAB would not affect it. Search under Sorbus and you will see there is a wide variety of species and cultivars. But I don't know whether they would be suitable for your region.

NO! Do not do a rejuvenation to any Viburnum!! Michael Dirr, who wrote the book on them and who has developed many of them, recommends infrequent and light pruning of Viburnums, if any at all. This is my favorite shrub. I have at least two dozen and about 8 different cultivars. I believe the one you have is a Burkwood, but it could also be Judd. Either way, it's gorgeous, pretty much pest- and maintence free, and you should definitely NOT coppice it. You do that to a Rose of Sharon or a lilac, but never to a Viburnum. Here is a link that might be useful: Michael Dirr's Viburnum for American Gardens

You can also see the opposite branching arrangement in the first picture. Agree that it is some sort of native viburnum. Could also be Viburnum rufidulum, but V. prunifolium has more range in Ohio overall as does Viburnum lentago.

#2 and #3 are correct. #1 genus is correct, species is tatarica. L tatarica and L morrowii are quite similar, the latter having hairy leaves. The two species will hybridize so separating the two can be difficult. L japonica is a vine.