in my opinion was a huge feature if we can chose in witch conner is the coordinate 0,0
For tile layers this option is partly covered by the following issue on github:
https://github.com/bjorn/tiled/issues/249
Or are you maybe talking about the alignment for objects? The alignment is currently top-left for rectangle objects and bottom-left for tile objects. Eventually I would like to introduce an option for this and unify these alignments by default.
Apart from that, you may be talking about the origin of the map, relative to which the objects are positioned. This is again something else and may be more related to the above issue with tile layers.
Eventually all these different things are related of course, and I’m not sure if it makes sense to arbitrarily combine all of them. So if you can provide any additional details in your suggestion this would be appreciated.