Star forward Jack Riewoldt kicked seven goals and the Tigers showed their enviable midfield depth in the 17-point victory at the MCG, but Hardwick said the Tigers had an enormous amount of work to do.
He praised the Tigers' leaders for steadying the ship in a tense fourth term, but said shallow forward 50 entries and a lopsided centre clearance tally (9-19) were concerns.
"We've got enormous scope for improvement," Hardwick said post-match.
"I've probably rated our guys a six-and-a-half or seven out of 10 tonight, and probably the same last week.
"The Carlton and St Kilda teams are around us from last year. We need to improve another 15 per cent to get to the sides above us again.
"Whilst I'm happy to be 2-0, I still know we've got an enormous amount of work to do in certain areas of our game."
Captain Trent Cotchin had 22 disposals in the second half to finish with 31 (13 contested), while Brett Deledio (27 possessions), Reece Conca (25), Dustin Martin (24) and Shane Tuck (21) were all strong contributors in an even midfield.
"Reece is a guy that we think has got enormous potential," Hardwick said of Conca, who is in his third season.
"He probably played his best game.
"Guys like Tuck, (Daniel) Jackson, these types of players can certainly go in there and hold their own.
"'Dusty' (Martin) had another pretty solid game, so we're happy with the depth in our midfield.
"I thought Cotchin, Deledio, Riewoldt … all our leaders were huge in the last quarter and got the game back on our terms a little bit."
After a goalless start to the season, Riewoldt continued an outstanding recent run of form against the Saints, kicking 7.2 from 10 kicks. In Round 10 against the same opposition last season, the spearhead booted eight goals in an eight-point win.
Hardwick said he hadn't made major adjustments to the Coleman Medallist's role after he was used higher up the ground against Carlton in the opening round.
"He still started up a little bit. Luke (McGuane) was pretty dominant early and then Jack went back," he said.
"The thing with Jack, he does play his best footy when he's up he ground.
"The pleasing thing from my point of view to sell it to him is he still kicked seven goals, which is great.
"There's going to be other games where he doesn't have the scoreboard impact, like last week, but he still plays well.
"It's a great learning for Jack but also our other forwards."
Nathan Schmook is a reporter for AFL Media. Follow him on Twitter: @AFL_Nathan
