Five-time Ballon d'Or winner Messi is the highest-scoring player in Barca's history, netting his 600th goal for the club with a magnificent free-kick in a 3-0 Champions League semi-final, first leg win over Liverpool on Wednesday.
The 31-year-old - contracted to the club until 2021 - took his tally of trophies with the Catalan giants to 33 by sealing La Liga glory last weekend, the first piece of silverware in a potential treble for Ernesto Valverde's men this season.
Barca will no doubt hope Messi is still around when the renovation and expansion of Camp Nou, which will see a roof added and the capacity reach 105,000, is completed in 2023.
Asked if a statue of Messi will join the one of Ladislao Kubala at the modernised stadium, Bartomeu told The Observer: "There will be 10 of them!
"I wouldn't even give him the Ballon d'Or. He's beyond that now, in a category of his own.
"There are great players, but he's in a different dimension."
And the team are on course to win a second European and domestic Treble in five seasons, with a Copa del Rey final against Valencia to come later in May as well as the second leg of the Champions League semi-final against Liverpool.
The title win marks Barca's eighth league victory in the last 10 seasons, and Messi has shown little sign of slowing down as he edges towards the twilight of his career.
His five Ballon d'Or victories is a record number for the award, an honour he shares with long-time rival and former Real Madrid forward Cristiano Ronaldo.