Two Player game - class buffs

[Helaman]

In a low player game gesalt is one option to give the characters more options (though not action economy). Another way is to give access to class features via background or items or give early access

I was thinking of allowing a Blackblade magus access to the sentient factor of the blackblade at level 1, to give advise etc (no access to bonuses, the awareness feat or allowing it perception unto level 3).

Is that unbalancing or problematic?