The game had quite a bit of slowdown, even on the pro. It was also a bit blurry at times with not so great anti aliasing. The frame rate drops made the game seem more clunky at times than it actually is. The gameplay doesn't need a great overhaul, it needs consistent 60 fps to back it up. One thing they could improve is the speed at which boy walks / runs. There should be something in between snails pace and brake your neck over every obstacle sprint pace.
Which shows team Ico is a little odd on their concern for graphics... so a remaster would need to be made by another studio =p
On the gameplay side, many people think it is a little bad so a work on it could help a lot.
The game have a very slow pace due to it.
duduspace11 "Well, since we are estimating costs, Pokemon Red/Blue did cost Nintendo about $50m to make back in 1996"
Mr Puggsly: "Hehe, I said good profit. You said big profit. Frankly, not losing money is what I meant by good. Don't get hung up on semantics"
Azzanation: "PS5 wouldn't sold out at launch without scalpers."