So, from lack of reply I take it most people would want Studio but do not consider the $100/year a fair price.
So let’s compare the pricing to similar subscription services and the cost of paid engines spread across 5 years.
I’ll look at only full packages comes with no limitations, just like what AppGameKit Studio would be
GameMaker Studio (spread cost across 5 years) = $89/year
Clickteam Fusion (spread cost across 5 years) = $129/year
Construct 3 = $116/year
GDevelop = $96/year
Stencyl = $199/year
GameSalad = $299/year
Buildbox = $599/year - if you also want monetisation features like AdMob,
Buildbox = $239/year - if you don’t want ads and in-app purchase also lots of other limitations
The average is: $166/year if we are not including the ridiculous $599/year price tag of Buildbox
Now, I do know for a fact, Stencyl, Buildbox, GameSalad and Clickteam Fusion do struggle so their prices probably worth excluding as well as it doesn’t work for them, which brings the total average down to: $100.33/year including only GameMaker Studio, GDevelop and Construct 3.
It is tells me $100/year is reasonable for full, unlimited access to all features and services.
However, considering TGC also do struggle and most people is not willing to pay $100 each year, then how about $75/year but not including monetisation features and $100/year for monetisation options? I mean if you plan to make money from ads then paying $100 is not a huge investment. Would that make sense?
Of course let's consider the possibility TGC would provide frequent updates and transparent roadmap in return maybe even some gifts to subscribers only..
To make subscription model even more attractive, TGC could also offer some free goodies, asset packs, examples, templates each month to subscribers only. Nothing big I am not talking about hundreds of sprites but only a few sprites, sounds, some code snippets..etc each month. This is what Clickteam is trying to do now with the Reactor subscription model and considered how much they ignore regular users and focus on Reactor subscribers only, I guess it may be working for them.
I have added Option4 to the above list to reflect this idea.