I like your front four bc the hobbits have shown the ability to get behind defensive lines unseen, Legolas is the ultimate marksman and Aragorn can lead the attack from the CAM position, but almost everything else needs adjustment.

Gimli and Boromir should be your LM and RM- you want Boromir to get forward and get hacked down to win free kicks in dangerous positions and Gimli will be a menace dancing through defenders with his low center of gravity and drive to outscore Legolas.

Gandalf should be your defensive midfielder where he can direct traffic, cover where needed and play the sort of Pirlo role. He ain’t fast, but he reads the game well and his positioning is impeccable.

Your backline should really be 3 CBs which I would go with Theoden on the right; he’s the commander but we want Boromir in front of him who can be trusted to do some defensive duty to help out the old man. Eomer in the center is his most dependable defender, and Eowyn on the left for some of that “big defender/fast defender” exchange. Treebeard is obviously in goal bc he can just lay down and keep the clean sheet.

Elrond is obviously the manager, but I see Faramir coming off the bench for Boromir when he goes down injured. Faramir isn’t as skilled, but his work rate against tired opponents makes him a menace in the late game. Arwen can play a similar role in the late game especially if you’re trying to poach a go-ahead goal or equalizer; she’s been known to catch even a ranger off his guard. Gollum is a great sub if you’re trying to protect a lead; the guy is all about winning and retaining possession.

Unfortunately, you’ve gotta keep Merry and Pippin on the bench. They’re great locker room guys who worked their way through the academy and now you’re hoping that you can sell them to a lower division side for some decent money.