According to a post by a Respawn developer on Titanfall's fourms the game will support multiple controller layouts which include Tactical and Halo fan-favourite Bumper Jumper.
Scriptacus wrote:
"There is a layout with melee and crouch swapped, as well as a variant that allows for jumping on a bumper. (my personal favorite, as it allows you to use the “look” stick while jumping). More than one controller layout confirmed!”
The Bumper Jumper layout allows players to utilise the controller's LB and RB buttons for melee and jumping; this particular layout first appeared in the Halo franchise.
Titanfall, which launches for PC, Xbox 360, and Xbox One on March 11th, will not offer mod support on PC at launch but the feature might be added later. It was also recently revealed that no-scoping and quick scoping sniping are "ineffective".