Daniel, there are close to no artificial limitations in full version, most of them depend on the system hardware and DBMS.
Our developers are working on removing all limitations that can occur, for example in 1C:Enterprise 8.3 number of concurrent sessions for file infobase was increased to 1023. Please compare with recommendation to use client/server mode after 5-10 concurrent users. The main problem is that when one of clients hangs in file mode, it might harm the infobase integrity, thus for reliability it is recommended to use DBMS.
There are software license keys for 1000 concurrent users, so you can rely at least on 1000 connections.
Please note that external connection requires a license same as thin, thick, web client, as well as web service (for time of execution only, so rarely will take more than one license).