The English back-rower will return home to play for Super League club Hull following four excellent campaigns in the NRL, which has seen him voted the Tigers' player of the season for the last three years.
And the 31-year-old is a huge admirer of NSW and Australia star Lewis, who will depart Penrith at the conclusion of the 2012 season, having been granted an early release from the final two years of his contract to seek a new challenge.
"He would be a great acquisition for the club, regardless of who is coming and going," Ellis told AAP on Tuesday.
"He is an absolutely brilliant player and by all accounts a great bloke off the field as well. He's the full package.
"He will have a big decision to make on where he goes but I would imagine every NRL club will be out to get him."
Tigers centre Chris Lawrence played with Lewis in last year's Four Nations tour of the UK for the Kangaroos, and said the 28-year-old would fit perfectly into the Tigers team.
"If the Tigers were lucky enough to get him we would all be delighted to have him," Lawrence said.
"He would definitely be a good fit for our side and a great player to replace Gareth."