I genuinely don't get the love for Xenogears. Between extremely slow text (in particular disc 2), boring gameplay systems, and graphics that are inferior to many other PSX RPGs I just never got it. There is a reason the game was less popular than many other SquareSoft games at the time. The whole experience just felt half-baked and it desperately needed some QoL improvements. Maybe I'd appreciate the game more now but I really disliked it at the time.
Chrono Cross is one of my favorites of all-time so that was my vote. So many people write it off as a poor sequel but I really think it is a far superior game in comparison to Chrono Trigger. Besides the things you would expect to improve over a 5 year span (OST, graphics, scope of story, etc...) the game is just more fun to play for me. The replayability of it is insane as well.
Front Mission 3, Vagrant Story, Parasite Eve, and Saga Frontier 2 all also deserve a mention.