Disney always own at least 2% of DVC units at any resort. The difference between an all-DVC resort and a resort with DVC stapled on is that the latter will have a large number of hotel units.
But as a fraction of the DVC units, the proportionality should be roughly equal across DVC properties. Riviera is fairly large so more cash units will be available after sell out than at, say, VGF, which is small. While only part of Riviera is declared to DVC, more units will be bookable cash.
Discounts will be far less frequent on DVC units in general, because Disney is starting with a far smaller fraction of them to get bodies into based on ownership.