As for the original OG RISC, I think that'd be the Cray 1.
So I'll go with the Cray as being to OG RISC. But yes, firsts don't really matter except to say it sure wasn't the Berkeley RISC or the Stanford MIPS.
uLisp could also take advantage of cross compiling, the author just chose another path that allowed him the focus on other areas instead.
Also probably most interpreted languages work out of the box (Ruby, Python etc)
Interpreter languages is easier, given the existence of C and C++ compilers.
What I would like to suggest is that once you basically “get” how the prefix syntax works, and how to process lists, Doug Hoyte’s Let Over Lambda (https://letoverlambda.com/textmode.cl/guest/toc) is a book that can really help you -learn- lisp, to fundamentally understand what makes lisp so powerful compared to other languages. Incredibly perspective-expanding content when I first read it, and largely references many of the “great” lisp texts that helped build the language and its community into what they are today.
For something like Common Lisp, which uLisp is similar to:
COMMON LISP: A Gentle Introduction to Symbolic Computation
Practical Common Lisp
Land of Lisp
ANSI Common Lisp by Paul Graham
SICP = Structure and Interpretation of Computer Programs
PAIP = Paradigms of AI Programming