A couple of questions from a SA:MP veteran.

[YonatanJ]

I've gotten used to SA:MP's limitations in scripting, so I'd like to know if the following is possible in MTA.

Creating a new map (actual ingame map, like instead of having the Los Santos map I'll be able to put a map I designed myself - not objects, but an actual map).

Creating new skin IDS (Note - more skinslots).

Deleting a city completely off the map.

Creating custom OBJECTS (actually designing the object's textures and placing them ingame)

[Callum]

All are possible, except for the third; creating new skin slots. You can however apply textures to pre-existing skins. Though you should look on a wider scale, of why to use MTA, as oppose to SA-MP. There are dozens of reasons.