Aston's major Imola update, which included a floor redesign, a front wing and diffuser, was shaken down by Fernando Alonso in FP1 before Lance Stroll also received the parts from FP2 onwards.
However, on a weekend where rival teams also wheeled out new parts or further dialled in those from Miami, Aston's upgrades may have delivered absolute performance but not relative competitiveness.
Alonso's weekend was derailed by a crash at Rivazza in FP3 and, following intensive repairs by the Silverstone squad, the Spaniard just about made it to the start of qualifying.
But another Q1 off at Tamburello led to Alonso being called into the box with further issues, ending the session in 18th place. With overtaking difficult, his race became a glorified test outside points contention as the team opted to make set-up changes and start from the pitlane.
Stroll didn't fare that much better by qualifying 13th, although he did get two points on the board by moving up to ninth.
According to Krack, Alonso's off-track excursions showed that its AMR24 is "difficult to drive" at the moment despite being slightly quicker after the upgrades.
"In Imola, when you start from where we started, it's difficult," Krack said after the race. "We come away with two points, I think it was quite a good outcome, it shows that the car is still capable of doing things.
"But we have also seen that it is difficult to drive. We had a couple of offs over the weekend. The one from yesterday was actually impacting us the most because we were really on the back foot from that point onwards.
"We wanted to learn more, that's why we elected to start from the pitlane and make a change on the car to see if we can make it easier. We wanted to do better from what we have done. But it was also compromised a little bit by the [Saturday's] events."
After qualifying, Stroll pointed out that the Imola upgrade package, which was described as being part of an "aggressive" programme by technical director Dan Fallows, was simply not enough to keep pace with its direct rivals.
Aston is in danger of falling further behind the top four while also seeing RB making strides since Miami.
But while Krack was careful not to jump to conclusions after Imola, suggesting the picture could look different in Monaco and again in Montreal, he acknowledged the AMR24 needs more firepower soon.
"We're not happy with two points, that is clear," he added. "But other people are also bringing upgrades, so it is always a relative game.
"It's tough, we must not underestimate that. I think, except one team, everybody has a list full of upgrades, so it shows how competitive the whole field is.
"We have to really keep pushing and bringing more stuff."
Additional reporting by Jonathan Noble
