Alfa started the 2023 season on the front foot with four points for Bottas' eighth place in Bahrain and team-mate Zhou Guanyu has also shown marked improvement compared to his 2022 rookie campaign.
But amid F1's extremely tight midfield battle, the Sauber-run team found itself on the wrong side of the points more often than not, having only scavenged points in four of 10 grands prix.
In Silverstone, where Alfa Romeo had brought a comprehensive upgrade package, it was demoted by Alex Albon and Williams to ninth in the constructors' championship, as Bottas' comeback drive from 20th to 12th was left without rewards.
For Alfa, whose C43 is a stable platform but still lacks aerodynamical load compared to its competitors, there are few signs of immediate improvement in Hungary and Belgium as the team's next upgrades will come after the summer shutdown.
"Definitely we made a step but also other teams need to make steps," Bottas said after the British Grand Prix. "That's the name of the game, so need to find a bit more.
"We don't have anything coming in the next two events but after the summer break, so the guys and girls need to work really hard in the factory to bring some new bits."
Post-summer upgrade aside, Bottas acknowledged that the Hinwil squad should start looking at whether its efforts are better aimed at its 2024 car or whether it is worth continuing to push with its current machine.
"I think at this point, we're approaching halfway off the season, and we've not been able to really move up the order," he admitted. "At some point, we'll decide when it's going to be 100% focus for next year. And I'm sure the discussions are going to be made soon.
"We were expecting to be better than last year, but we just didn't find enough during the winter and the beginning of the season so far.
"We're not meeting the targets we've set ourselves."
Trackside engineering director Xevi Pujolar said the team's Silverstone upgrades, which included changes to the floor and the rear end of the car, had delivered as expected.
He was adamant that with Alfa now hitting the budget cap, it has made a "big step" but admitted another one is needed to break out of its current position.
"In the factory, with the production and everything, we're now level with our competitors on all areas," he said.
"It was a big step, for sure. But it's still another step to go to progress. As you can see, we're still fighting in the midfield."
