Arsenal, third last season, appear better-equipped for a title tilt, while Manchester United, Manchester City and Liverpool have spent big in the hope of closing the gap on Chelsea, who finished eight points clear of outgoing champions City in May.
But with their title-winning side intact, Jose Mourinho's men are widely perceived as the team to beat.
“Throughout the Premier League there is strength now because a lot of clubs are buying big players, not just the top clubs,” said Mourinho, who hopes to repeat his feat of leading Chelsea to successive titles in 2005 and 2006.
“At the moment, we are champions of the toughest league in the world, so we know how difficult it is going to be to repeat the achievement, but we are ready for the challenge and we will enjoy the challenge.”
With Asmir Begovic having replaced Petr Cech as reserve goalkeeper and Radamel Falcao taking the place of Didier Drogba, Chelsea's squad is materially the same as it was last season.
However, Diego Costa's troublesome hamstrings, which caused him to miss Sunday's Community Shield loss to Arsenal, and some leggy pre-season performances have given their rivals reason for optimism.
That 1-0 Community Shield win, coupled with the arrival of Cech, has encouraged belief at Arsenal, back-to-back FA Cup-winners, that their 12-year wait for a league title may be approaching an end.
With a world-class goalkeeper backing up a settled defence and a midfield that bristles with guile and inventiveness, the only weak spot is up front, where Arsene Wenger must choose between the not particularly prolific trio of Olivier Giroud, Theo Walcott and Danny Welbeck.
Another team brimming with midfielders and short on strikers is United, with Louis van Gaal having added Bastian Schweinsteiger, Morgan Schneiderlin and Memphis Depay to a department of his squad that already included Michael Carrick, Ander Herrera, Marouane Fellaini, Juan Mata, Ashley Young and Adnan Januzaj, not to mention the departing Angel di Maria, whose place in the squad could go to Barcelona's Pedro Rodriguez.
Falcao, Nani and Robin van Persie have also left, but as a Champions League qualifying play-off looms, goalkeeper David de Gea's future remains up in the air.
With a new £5.1 billion ($8 billion, 7.3 billion euros) domestic television rights deal kicking in next year, Premier League clubs have not been shy in splashing out.
The biggest transfer to date has been Raheem Sterling's £49 million switch from Liverpool to City, after a protracted transfer saga that opposition fans are unlikely to forget in a hurry.
Despite falling short in defence of their title, City have kept faith with manager Manuel Pellegrini, but with the club hierarchy continuing to flutter their eyelashes at Pep Guardiola and last season's Golden Boot-winner Sergio Aguero short of fitness after the Copa America, doubts remain.
Shorn of Sterling and the emblematic Steven Gerrard, Liverpool have brought in seven new players, among them Christian Benteke, James Milner and Roberto Firmino, but ahead of an opening-weekend trip to Stoke City, where they were humiliated 6-1 on last season's final day, manager Brendan Rodgers is also under pressure.
For all the title contenders' big-money moves, it is the transfers involving England's mid-ranked clubs that have emphasised the Premier League's transformation into a financial behemoth and none more so than Yohan Cabaye's £10 million switch from French champions Paris Saint-Germain to Crystal Palace, who finished 10th in 2014-15.
With even the smaller teams now boasting budgets that put them on a par with all but the very biggest European clubs, a whole host of sides – among them Tottenham Hotspur, Southampton and Everton – will have designs on the European places.
Stoke and Swansea City will hope to build on impressive campaigns, while Palace, Aston Villa, West Bromwich Albion and Sunderland finished last season dreaming of better things after successful managerial changes.
West Ham United, Newcastle United and Leicester City have new managers -- respectively, Slaven Bilic, Steve McClaren and Claudio Ranieri – as well as Watford (Quique Sanchez Flores), who were promoted from the Championship alongside Bournemouth and Norwich City.
“It's not rocket science,” says Bournemouth's affable 37-year-old manager Eddie Howe.
“Bournemouth are not going to be able to compete with those top clubs, but when you put 11 players on the pitch, it's not really about money.” – AFP
Original source: Chelsea favourites to retain title