My brother and I played the ever-loving hell out of UA3 when it came out. We must have put 100+ hours into it. It was a blast, though extremely challenging in some instances. We had a Ghost Rider and Psylocke combo that just absolutely wrecked shop. I will say the game gets way too in the weeds with the whole ISO-8 crystal shit or whatever it is, making us spend far too much time with managing upgrades and inventory instead of just whooping ass. We played a lot of X-Men Legends and Ultimate Alliance as well, still did up until pretty recently too.
It's funny, we game together a lot but we don't ever really get too hung up on nostalgia for older games because we never stopped playing those older games. We still play everything from NES to Switch 2. It's kind of like with my toy collecting, I've always collected toys so I don't get too nostalgic for older toys I used to have because it's like my newer versions are so much better, and I still have nearly every figure I've ever acquired since the early 2000s. Not really much chance for nostalgia if your collecting or gaming or reading or watching journey is still one unbroken path.