Its possible to work on 2 games at once, but you need to be efficient and organized. Mr.Dots obviously does it very well. SuperWriter has done it well so far. PTOLEMY works on several games at once. The common theme? 2 of those guys have development teams. SW is a part of a development team, so he could be getting help too.
I think, for this and Alison, it would be best to adopt a 2-1 update schedule. 2 updates for Alison (since its more complex) for every 1 update of Shrink. Shrink-Alison-Alison-Shrink. I saw he is planning on weekly releases. That could work, but it creates a lot of time pressure.
It would be smart to make the routes in Alison less complex. The way its done now, he isn't really working on 2 games. He is working on 4 games since the 3 different Alison routes are basically their own game. The routes can still be different obviously, but not completely different. It creates unnecessary work, try to simplify things and cut the fat.
I would say to not make the trans girls in this game into regular girls too. I know he has said what he can handle, but you shouldn't do things just because you can. Like I said, its all about being efficient. If people don't like trans girls, just let them avoid their content.
He has frequently mentioned support levels recently. If you are trying to please everyone (like making regular girl versions of the trans girls) you'll end up not pleasing anyone. This is also partially related to Alison, as it is basically 3 different games, the updates for the game may be frequent but the updates for each route aren't frequent. It would be better to streamline the routes, make them simpler , so he can update them all at once in a reasonable time frame. A game that does this well is
Ataegina. It has 3 distinct routes, but are similar enough that they can be updated at the same time on a reasonable time frame. If someone is thinking of supporting, but their preferred route isn't updated often enough, then they won't support it.
And that concludes my completely unasked for opinions, advice and random ramblings.