All weapons are good if you learn how to use them. If you want something that isn't as slow as the hammer and great sword then the sword and shield or the switch axe will be good. Bowguns will also be good since you'll have plenty opportunity for ranged attacks while the monster is focused on your friend.

Hammers.  Man, I use to hate them.  Once you understand how they work, they are ridiculously good.  Versatile as hell and extremely powerful.

I wouldn't mind using the sword and shield, but I think I rather use the switch axe. That thing looks bad ass.

Try the Switch Axe, it's a new weapon so it's as fresh as it gets.
 
The hammer is strong as usual so that's not a bad option either.

I am liking time with the hammer and with the sword/shield combo

Lance all the way, it may not do as much damage as some others but when you can use it well you become invincible.

I use LS, and alternatively DS.

The Great Sword destroys alllll!! Easily my favourite weapon so far but I love all of them. Started using the Hammer and it's my second weapon of choice. The Lance is also pretty dope. Haven't built a Long Sword yet, but loved it in MHFU.

Great Sword is tried and true favourite of mine. It's all about timing and the satisfaction of getting off a level 3 charged shot right on the monsters weakest point is bar none the most satisfying thing you can do.
 
Just keep a few points in mind with your great sword:
 
-have that motherfucker sheathed at all times unless you're drawing it onto the monsters face
-dont bother walking around with your sword unsheathed unless you're rolling away or about to block something [hey there Barroth]
-if you got a large opening draw out into a charge attack, make sure to let go of the button when your character glows white and he should do a level 3 charge. it should be indicated by the sound and the white flash coming off your dood.
-If a small opening turns into a large, just combo it out into a charge by pressing X, X and then hold the directional stick some direction and press X again, this'll do a backside-kind-of charge, the most powerful hit in the game if you do a level 3 charge.  [I think it's X, whatever Triangle Equivocates to on the Classic Controller, too used to PSP!]
 -After landing any large attack from overhead, roll out to stop the long cooldown time of your character looking at this massive sword stuck in the ground.
-what are you doing walking around with that thing out in your hands? Sheathe that dude! 
-If you're online NEVER use the overhead slash, the one that you press X and A for. It'll throw your buddies into the air, and its not worth it, when you can just press X again after your unsheathe attack or if you really want to, press A for a sideways area attack.

I like the Sword and Shiled it's as quick as the LS (quicker) and reminds me of the LS. I'm usually using the LS or SNS.

I really liked using Dual Swords in MHFU, but they're apparently not in this game. What would be a good substitute for this?