It may be a while before any other steam gauge 172’s come out as the entire deluxe pack is about the same price as just one payware 3rd party aircraft so there may not be a lot of demand.
I am sure eventually someone will sell one that has a few extra’s like floats and a tundra/taildragger version to distinguish it from the generic MS version but it may be a while.
In terms of GA singles, the Bonanza with the freeware improvement mod or the turbo mod are both good, the Jabiru pack and Carenado Mooney on the marketplace are reasonable options and there is a really good version of the Piaggio P149 you can buy direct. Also both Carenado and Just Flight have Piper Arrows due for release soon.