Don't you miss the flash games
No not really and besides the arcade has already been shown to have unique games using the new coded OS.
The basically abandoned casino
Definitely not, at least now I see some interaction amongst players sat next to each other.
The computers had an OS
This is actually in development, perhaps you should watch some of their dev streams sometime...
The new OS also allows for some advanced stuff that GMT could only dream of.
TU is currently kinda...a bit linear with its shops
I don't even know what you mean by that, you want the shop to be complex and hard to understand or simplistic with ease of access...Because I'm pretty sure most if not all will choose the last.
By the way, not personally jabbing at you. But from the history of your suggestions and posts you should probably check their current development as a lot of the things you're suggesting and discussing is in the works...