Honestly the biggest problem with Elpis is that we are allowed to interact with it. When Elidibus was sending us back and we showed up as a tiny ghost I thought we were just going to observe and learn. I was fully prepared to sit there for 2+ hours and just collect information, completely unable to do anything as I view the memories before me. The moment I can talk to the past and it responds to me, I'm changing a lot of things. I really don't like the idea of "the past cannot be changed." We know that it can in this setting and have already done it. But it gets worse. Way worse. After we have defeated Meteion, we can still go back and do so with Pandemonium. We know where she is, what she is doing, how to stop her, and can potentially just do so (hard to say because Elpis technically changes how our power functions), but we don't. We continue to not change the past for "reasons." That's my problem with Elpis, you want to give me a fun map to explore in the past, but you don't want the obvious implications that brings. If you don't want alternate timelines then don't let me shake hands with a memory.