Which is serve as a nickelbacker who is a passing game specialist, he wouldn't be getting elite ILB money. Guys who get the top money there are sound tacklers and fillers in the run game plus can execute the scheme vs the pass. Littleton is average at best filling run fits and below average if there's any sort of stack & shed required.
The team who offers him the most on the market will probably be a 4-3 team that needs a WILL as he's an excellent tackler chasing and in space and is elite in coverage.
Paying him will be similar to the Rams paying Ogletree. It will be a mistake. He's a better tackler than Ogletree but like AO he does not have the ability to fill hard and downhill vs the run. Without that you are better off from a team building aspect to draft nickelbacker types to fill that role and they are available in every draft.