O'Neil said: "The new coach and fresh ideas, they've got (Ebrechi) Eze and (Michael) Olise back, Marc Guehi coming back. Roy Hodgson did a fantastic job for a very long time. The changes are not only due to form are not only due to change of coach.
"The combination of both, good coach, new ideas, best players available, it will be a tough test for us, they're on a really good run. A last home game that we want to be enjoyable for us and the fans. A chance to go out on a high."
On Palace pair Eberechi Eze and Michael Olise, he stated: "They look like players that could play at the very top end of the Premier League.
"I'm sure Crystal Palace will be desperate to keep hold of them in the summer. They're in the sort of form where everyone will be talking about them, big clubs will be looking at them."
O'Neil admits Pedro Neto will miss the game.
"Santi (Santiago Bueno) is better. He only trained on Friday last week so wasn't available to start at City. He's fine now. Pedro (Neto) still won't be involved tomorrow. He's training, but not done enough at high speeds to guarantee it's not a risk for him at this point. Apart from that we are pretty good.
"The change in results and momentum shows it has impacted us. No excuse of course, we understand all teams have injuries. To have no forwards available for a long part of the season is tough in the Premier League."