NeuroVoider

Arcade mode is easy difficulty pretty much. The game can be a bit challenging at first but if you stick with Fortress using the Self Repair skill, you shouldn't have too much trouble. Only spend your points on upgrading orange items. Equip your character with the best items until they are orange, then upgrade them. For weapons, I like to stick to using dual rocket launchers and fully upgrading them as the damage is insane. Especially against the boss fights.