The Ranger is a generalized suit designed for up-close and personal combat. It has a large club like melee weapon plus an ultimate that fires an arsenal of missiles.
The Colossus is the heavy suit that brings the big guns to the fight, like a mortar. It is also capable of deploying a shield to protect itself against heavy damage, while its melee ability is a ground slam that does damage to multiple enemies in an area.
Not much was shown of the Interceptor beyond it being a lighter, more maneuverable Javelin. The exosuit was not present in the four-player Anthem gameplay segment.
Meanwhile, the Storm suit appears to utilize an electromagnetic field to hover and fly plus suggested unknown electricity-based abilities. The gameplay trailer does show a Destiny-like blink ability to quickly teleport a short distance.
Players will be able to freely swap between the different Javelin types in Anthem, but only outside of missions. This means only one character will need to be created to get access to everything.
Anthem is designed out of the box to be a co-op experience. The game can be played solo, but will be more difficult. However, Fort Tarsis will serve as a solo hub like the Base of Operations in The Division. The Fort will be there for narrative purposes, though the vendor setup is unknown.
BioWare clearly plans to make combo attacks a major portion of the game to use against tough enemies and likely bosses. There's no word on how many interesting combos can be built around the different Javelin skill trees.
Executive Produce Mark Darrah, unfortunately, confirmed there will be no underwater combat in Anthem during an interview with Game Informer. The underwater sections of the game are for travel only.