Doing C16 games isn't that straightforward. For a VBXE system it gets a bunch easier.
The 2 main obstacles are -
. 256 characters. This is probably the biggest one. For a game where arbitrary character placement can occur it's a big problem. With VBXE you can just have a virtual character map and use blits to do bitmap conversion of the entire screen.
. attributes. The C16 has a minimum of 1 byte of attribute for every character cell, so can use half or all colours as a foreground colour depending on mode. Again, VBXE can deal with this.
The third obstacle is dealing with Plus4 64K games. Potentially they can use all of the Ram and when there's no free holes it leaves little scope to put in your emulation layer.
The other thing as mentioned various times - the games, especially 16/32K ones aren't particularly good. And in cases where an Atari version already exists, often not worth the effort.