So you can make AT on a platform to do a very specific set of smart contracts and not others, right? So a dev can pick just which kind of smart contract the platform needs and no more, and if there is not code for that smart contract, it can be made?
AT supports "generalised smart contracts" (so there is no specific set or limit to what can be created).
In the case of Burst some user friendly HTTP forms are being created to help non-devs construct ATs from a specific set of "templates" (and this approach makes sense to let non-programmers create ATs).
The only thing that "limits" a dev is their understanding and ability to actually write an AT either from scratch or from an existing use case (currently they are written in an "assembly language").
We have plans to use LLVM in order to generate AT compatible machine code which would actually let people write ATs in C++ (something I don't believe even Ethereum can offer as they are instead focused on the idea that everyone should learn a new language and also use a new browser which is not the way we think things should be done).