Yes, Aeons/ Yu Yevon are a pushover, because its a story battle. Not to say Jecht isn't a pushover either. Like FFVII, this game seems to spoil you greatly. (Although the side-quests are kinda annoying.)

Yeah, try out X-2. It pales in comparison to X, but its still okay. (But...the story...is...ugh.) Well, at least see if you like it.