What difference would altering the starting level even make?
As far as I am aware you can't avoid the fight with the three intellect devourers after the tutorial without having to resort to stealth or some acrobatic jumps (AKA methods barely anyone is going to attempt on their first blind playthrough) yet you have amassed enough XP to reach level 2 upon beating the encounter. From there on you have a handful of opportunities, all of which quickly will result in you levelling up again due to the very small amount of XP you need for the first handful of levels.
This means that by the time the game starts to 'open up' and move out of the initial post-tutorial area you're already level 3 or close to reaching it. You should be able to live without the benefits of being level 3 for the first one or two hours of the game.
