Coach Rudi Garcia, the man behind the free-flowing football that took the club to the Ligue 1 and French Cup double, will stay next season but Ivory Coast striker Gervinho and influential French international midfielder Yohan Cabaye have yet to be confirmed.
Where to play their Champions League home fixtures is also a worry for the northern club. Their new, 50,000-seater stadium in Lille will not be ready for another year and their temporary home, the Stadium Nord in Villeneuve d'Ascq, has yet to receive approval for European matches from governing body UEFA.
The nearby stadium of fellow Ligue 1 side Valenciennes could offer a solution.
"We will try to play at the Stadium Nord but UEFA have yet to approve it," club president Michel Seydoux told Reuters. "If they don't, we will go elsewhere. It will be Valenciennes if needed but I'd rather play in Lille."
Lille do not have the financial clout of their counterparts in the Premier League, La Liga and Serie A and fear losing some of their leading players who have been targeted by richer European clubs.
"We will never be at the same level as other European clubs," Seydoux, who took the reins in 2002, said.
NEW REVENUES
"The club's budget will increase in the coming years. It should be around 80 million euros (from 55 million euros this season) next season and around 100 million in the coming years thanks to the stadium.
"The stadium will generate new revenues and that is crucial because we cannot just rely on the TV rights."
Money was not the only necessity for success, however, Seydoux said.
"We can develop ideas others don't have, we can be smarter to find the best players, we have the ability to go and get future talent," he explained.
Belgian prodigy Eden Hazard, who scored seven goals and created 10 this season, is one player who will stay.
"I am not thinking about transfers. I have many contacts but my advisers and the club are the ones controlling that side of things," said Hazard, who joined the youth academy in 2005.
The 20-year-old Belgian, twice voted the best prospect in the French League, has arguably been Ligue 1's top player this season.
His delicate turning and his ability to find his striking partners Moussa Sow and Gervinho proved devastating to opposition defences, who conceded a total of 65 goals.
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