More than a decade on, he has his eyes down for a new challenge: injecting Companycare Communications with 'fresh thinking' in his new MD role at the Reading-based agency.
Maguire - an approachable 39-year-old with four kids, a passion for tea and American comic books - took up the position last month, after 14 years in his native London at QBO Bell Pottinger (and its predecessor guises).
The appointment of Maguire - 'I think of myself as a creative spark, a catalyst' - has allowed agency founder Ian McCann to become chairman and CEO at the consumer, corporate and tech agency.
Despite a glut of awards over its 20 years, the agency, which has clients such as 3M and Siemens, 'hasn't always banged the drum', Maguire says.
He admits: 'I think the agency is fairly invisible - it's for me to do something about it.'
In the latest PRWeek Top 150, Companycare was shown to have 25 staff and turnover of £1.6m; a full decade ago, the agency had 19 staff and turnover of £1.1m.
Admirably stable stuff, but - keen to transpose a 'big agency' mentality from Chime-backed QBO - Maguire asserts: 'I don't want another year of "the same".'
'There should be no fear in taking on a brief. We should be more self-confident that we can hold our own against (bigger) agencies,' he says.
Brought up in Wandsworth and Putney, Maguire studied politics and industrial relations in the mid-1980s at Kingston Polytechnic.
After a spell 'loading lorries' for a bathrooms firm in Waterloo ('being a fairly big lad, I was more brawn than anything else at that point...'), his first PR job was at 'one-man-and-his-dog' Shaftesbury Avenue agency Barrett PR.
He then joined the former Welbeck Public Relations ('a massively different world'), working in sports sponsorship for clients such as Gallaher and Courage. Later in his career, at QBO, he enjoyed promoting Autoglass's sponsorship of Chelsea Football Club, his favourite team.
Before that, finding his sport work at Welbeck 'very demanding in respect of time', he moved to Granada Leisure, on a press office job that involved promoting the joys of bingo. 'I used to love working in the bingo area - getting to know the people. I remember bingo-calling in Stratford in east London - a vocal environment, but great fun,' he recalls, with genuine passion.
He joined The Quentin Bell Organisation as a senior account executive in 1991. Then MD Trevor Morris (later CEO of Chime's PR businesses) interviewed Maguire for the job and today remembers a 'fresh-faced youngster' with a 'calming' habit for saying 'anyone fancy a brew?'.
Morris, now a schoolteacher in south London, adds: 'Paul is a people-person - he has a youthful enthusiasm and will say "hello" to everyone.'
Maguire says he has a fondness for 'campaign-driven work', remembering past clients such as Direct Line and British Gas where 'we could tangibly see PR making a difference'.
Morris says: 'Paul can popularise things that may sometimes appear dull. He has a mid-market tabloid instinct that was suited to that British Gas campaign.'
How does Maguire feel agency life has changed since the early 1990s?
'It was a lot freer then - more sparky, more energy,' he says. 'A lot of dialogue today is about energy and value - let's not lose sight of what makes PR different: spark and creativity.'
On that topic, Maguire says he is 'restless in terms of ways to improve what Companycare is doing. Are intros as good as they can be on copy?
Are we visible? Are we on pitch lists for big brands?'.
But he concedes: 'It's hard to tell agencies apart these days - there's a much of a muchness.' His task, he accepts, is to make Companycare stand out from the crowd.
1987: Graduate trainee, Barrett Public Relations
1988: Account executive, Welbeck Public Relations
1989: Press officer, Granada Leisure
1991: Senior account executive, The Quentin Bell Organisation
2000: Director, QBO
2003: Director, QBO Bell Pottinger
2005: Managing director, Companycare Communications