All gamers have to start somewhere, we all know the awkwardness. You're sitting a table with a 1st level character hoping that a goblin doesn't roll a 20 on their first attack. You've got no skills, no cool gear, just some crappy hit points, no saves to speak of and maybe if you're lucky one or two good stats.
A good number of us make gimmick characters and try to be funny. A rare few get past just stabbing people and cracking jokes. Meriadoc Brandybuck is one of those rare few.
Merry started as part of a gag party, let's be honest how long do you think three halfling thieves are going to last? The party was so lopsided the DM had to throw in a DMPC in Sam, and had to invite somebody to play a more experienced warrior character in Gandalf. Merry starts off with his partner Pippin running around and being obnoxious, just like 1st level characters are wont to do. Even after Gandalf has to start working evenings and can't play any more and is replaced by the LE Ranger Aragorn, Merry is more concerned with having fun than progressing the plot. He steals from all sorts of NPCs, and violates the first rule of setting up camp along with Pippin and DMPC Sam by making the party unnecessarily visible.
All that changes once the party gets to Rivendell. Here new players join and Gandalf can finally start making game sessions again. Instead of the cold and emotionless Aragorn Merry is now tutored by the warm and friendly Boromir. Merry makes a conscious realization that the party doesn't need three thieves and multiclasses to fighter under Boromir's tutelage. Old habits die hard though when he again gives away his position to the Watcher in the Water and nearly gets the party killed. Merry then swears to stop goofing around and starting actually roleplaying.
Unfortunately for Merry other factors are at work, and after Aragorn conveniently lets Gandalf fall to apparent death and then is intentionally too late to save Boromir, Merry is kidnapped with Pippen by the forces of Isenguard and then promptly forgotten about by Aragorn. Merry starts to play smart by feigning unconsciousness so he can quietly look for a way out. When Eomir provides a distraction he's finally able to make his escape. Then Merry realizes Aragorn isn't coming. He does the math, somehow super ranger Aragorn can't catch up with malnourished Uruk-Hai that are exhausted despite a marginal head start for three straight days?
Merry shows that he's been spreading his skills around when he has to explain to Pippin inxay alkingtay on the ingray and gives the history of the trees that move. Both characters have been together from the start, this is common knowledge. But where Merry wisely put points in Local Knowledge and Gather Information, Pippin has squandered his skills by dumping all his spare points into Profession: Ecdysiast. Merry finally makes his break and drags Pippin with him where they are able to get help from the friendly and completely randomly placed Ent Treebeard who just happened to be the one tree they climb when they are getting owned by an orc.
Knowing Treebeard is an attempt to get this plot under some semblance of what the module calls for, Merry goes along with the DM's plan and runs with it. Gandalf's player is able to make a brief one session appearance, having healed from the falling damage and replaced his ruined robes. He warns Merry and Pippin away from the murderous ranger, and to stick with Treebeard, then gives Aragorn some made up story about how Gandalf died and was reborn so is now immortal so Aragorn won't try to arrange any more accidents. Fortunately Gandalf sends Aragorn on a wild goose chase away from the hobbits, so Merry is at least safe from his wrath.
The DM concentrates on Aragorn and his bunch as they are the more experienced and more fun according to the DM. Merry spends his time wishing something would happen while Pippin still just runs around being goofy. Merry's player starts changing Merry's planned level progression into more strategy and tactics than just pure damage. Merry learns from the highly intelligent Gandalf's straight fighter build that you don't need a high strength to be an excellent fighter, that intelligence can be just as dangerous to unsuspecting foe.
Merry gets thrown a bone when the DM has Treebeard discover Saruman's destruction the Fanghorn Forest, and gets a front row seat to the March of the Ents. While all he gets to do is occasionally make an attack roll with a rock, he does get to make a joke about Saruman regretting waking up to mourning wood. Finally Aragorn shows up and discovers Merry has already defeated Isenguard, so now Aragorn has no excuse but to take the hobbits with him.
The reunion is brief as Pippin is still in his unfunny prankster mode gets messed up playing with an artifact so Gandalf takes him off on a side quest which is mainly an excuse to keep him from causing any more chaos in the campaign and teach him how to roleplay. So Merry is off with Aragorn, Gimli and Legolas to go fight evil. Only Merry is much more serious now, and getting to be a decent roleplayer. Aragorn has a bit of a snit when he finds out he's under Theoden's command and scarpers off, taking everybody in the party but leaving Merry behind because Aragorn really hates people that roleplay actual characters instead of just fleshy parts of swords. Fortunately Merry gets Aragorn's left overs when Eowyn takes a shine to him. Roleplaying to the hilt Merry wins her favor and charges into battle with the Rohirrim, mostly to spite that prick Aragorn.
Merry's evolution comes to its fruition when he finally faces a big boss by himself, with only the NPC Eowyn to help. Merry knows Eowyn is supposed to be the one to kill the Witch King, she's the ONE and PCs need not try to steal her thunder. However Merry was paying attention to the exposition earlier and remembers no man can kill the Witch King. While arguing semantics over whether hobbits are a separate species from men and therefore no held to the same restrictions would be pointless as the DM wants to show the party how badass his NPC in Eowyn is, Merry has a brilliant idea. Merry argues the prophecy says no man can kill the Witch King. It doesn't say anything about non-lethal sneak attacks to the undead kidneys however. Merry doesn't strike the fatal blow, but he lets the SOB know that Merry wasn't going to let that boss fight go by without taking his pound of flesh. DM is livid about Merry using logic and stealing part of Eowyn's glory so he makes up some lame excuse about an undead aura that severely wounds Merry and destroys his magic sword in retaliation. Doesn't matter, Merry is his own hobbit now. We should all be like Merry.