I actually worked for a while using a macro language written using the really very powerful macros in assembler H to implement many high level procedural language type constructs. (This ran on top of an "in-house" tp monitor written in the 60's for Southern Pacific railways a sort of pre-CICS effort)

Never managed to get any EXCP io accesses working, my one attempt failed and due to deadlines got quickly replaced.

CICS was quite interesting since on it's front it was quite simple but in reality it took a good knowledge to design a robust application (TDQs (intra partition or extra partition), TSQs (main store or not), the co-operative multitasking nature (Which they changed on OS/2 to be pre-emptive and thus stopped direct porting of many apps). Very interesting was the pseudo-conversational nature, which of course mirrors very much the nature of web-development...

Also did a fair bit of development with Adabas-Natural a good database on the mainframe and pretty flexible 4GL.

I'm a little suprised you haven't mentioned CLISTs for scripting which predated rexx by quite a bit. Combined with all the calls to integrate with ISPF (file tailoring etc.) made it a pretty useful tool in it's time.

These days it's mainly Oracle PL/SQL, Java and a bit of Perl or PHP.

I'm reasonably impressed overall with Java but don't like the amount of casting required to get things to work, nor the amount of converting to the object types of Integer (int) etc. to do certain things.