McLaren was fourth in last year's constructors' championship after improving significantly over the season.
That improvement and ongoing optimism within the design office have left Brown enthused about his team's prospects heading into 2024.
“We'll just keep doing what we're doing,” he told Speedcafe.
“We know we can only control what we can control, and that's our racing team.
“We like what we're seeing in the wind tunnel and CFD at the moment. So we feel like we're going to take a step forward.
“How much? The great mystery on Red Bull is when did they turn off the development of their  car?
“I think the answer is probably pretty early, so we'll just have to wait and see how much Adrian Newey magic comes out of the oven, so to speak.
“At the same time, Mercedes, Ferrari, these teams have everything they need and they're great teams.
“I wouldn't be surprised if we were sitting here and all of a sudden Mercedes was back to Lewis [Hamilton] winning a championship.
“It's very, very tough and competitive.”
McLaren has retained Piastri and Norris for 2024, both on comparatively long-term contracts – the latter having renegotiated his deal in recent weeks.
The papaya operation has already unveiled the look of its new car, with a more traditional car launch scheduled for February 14.
That car, the MCL38, will likely be an evolution of the MCL60, with the arrival of key technical staff too late to impact the new design significantly.
The squad has, however, ameliorated from its new wind tunnel and simulator coming online during the 2023 campaign.
And though that offers some gains for the coming year, it will only truly offer its full value when it comes to developing the 2025 car.
“We kind of have everything we need now, but '24 is still a hybrid year,” Brown explained.
“While January 2 I've got everything that we need, you really needed it June 2 if it was going to be full impact in '24.
“So I think '24 is a little bit of a hybrid year for us, but no excuses.
“We have the desire to be winning races, but it's going to be '25 where we can sit there and say ‘everything in '25 has been done with our full capacity of technology and people.'
“And that's not that far away.”