Gatland took charge of the Lions for their tour of Australia earlier this year, coming away with a 2-1 series win thanks to a team dominated by Welsh players.
His selection drew criticism in some quarters and Gatland believes a discussion is needed about what fans want from the team.
He told the Sunday Telegraph: "I think something the Lions should instigate is a public debate about whether the Lions need a quota system.
"It's worth debating and I think we should start it off. Do we need a minimum number of players from a country in the squad and then, when we are picking a Test side, does there need to be a minimum of one or two [from each country] in the starting XV?
"I think I know what the answer will be with that, but, if we don't raise it and debate it to get a consensus, then potentially we are going to end up with what we had recently on this tour."
Gatland was surprised by the vitriolic response his team selections inspired in come quarters, with suggestions that his choices were anti-Irish or overly pro-Welsh.
"That personal stuff got to me," Gatland said. "I go back to the 1993 Lions tour to New Zealand and I think there were 11 Englishmen that started the third Test in Auckland, but there wasn't the controversy with that."