ASM is extremely diabolical, because you can't exactly identify everything(probably because people are too busy having a life than documenting a 22 year old executable) and a lot of stuff is just set which is why for example, that ORG16 cannot be implemented via ASM because the sound buffer thing it uses is in .data and it can't be changed(I think), PEONS might be able to create segments and stuff, but I don't think you can just full on replace data like that and plus, I rarely ever see PEONS mentioned, let alone used in hacking.
CSE2 is better but you need to know C++ and you also have to use mrmap.bin which you can only get from Booster's Lab but the version is buggy...