"There is still a lot of room for improvement," England international Walker told BBC Radio 5 live. "I have read some articles that say we need to win things continuously for a number of years before we are classed as a great team.
"Every single one of us wants to be recognised as one of the greatest teams to play in the Premier League."
City's march to the title and their League Cup triumph in February has been offset by a shock FA Cup exit to Wigan Athletic and the 5-1 aggregate defeat by Liverpool in the Champions League quarter-finals.
"If we concentrate on ourselves then as a team we can go on to great things," Walker added. "But the Liverpool game(s) showed us that we are not a perfect team."
The 27-year-old also credited perfectionist Guardiola for City's free-flowing style of play, which has led to their domestic dominance.
City can sweeten their title win by breaking several records in their five remaining league games, starting with Sunday's home match against struggling Swansea City.
(Reporting by Aditi Prakash in Bengaluru)
