Tough call. For me, if I were doing a programming language, I'd probably go with the Apache License or something. I like the GPL and other copyleft licenses, but don't want to deal with the confusion around "Are binaries produced by the compiler bound to be GPL'd" kind of questions. I think GCC even ships with a "GPL + some special extra verbiage" license if memory serves correctly. Me, I don't want to deal with "special extra verbiage" because I'm lazy. But it really depends on your ideals / goals and what-not.
If it helps, there are a couple of (free) books out there that run through a lot of explanations of different OSS licenses and the benefits and tradeoffs of each.
https://people.debian.org/~dktrkranz/legal/Understanding%20O...
https://www.rosenlaw.com/oslbook.htm
There's also "Producing OSS" which may be of interest to you: