Thanks for your thoughts by the way.
If you wanted that to be your characters story shrug reflavor away gungadin.... Being able to posess a nobody and elevate them to a reflection of your status is probably a built in ability.
HOWEVER - If you were these arrogant potent items as mighty as a hero in your own right would you want to be bonded with that peasant who really isn't contributing anything to your symbiosis.
And you still would want something like the abilities which allows you to absorb other magic weapons (transfer their enchantments to you and similar abilities).
I think there is plenty of interesting elements for a race with a classic but different flavor to it.
It is simply that a low level commoner is the one mostly likely to pick you up since they are the most numerous, chances is are that a low level commoner is the one that is going to pick up that sword, and also they are the ones mostly easily defeated in an ego contest, that an intelligent sword can control. Now this works best of the goals of the peasant and the goals of the sword are somewhat aligned. The peasant has some problems, he has a family to feed, he has to deal with the lord of the holdings he farms and give a percentage of his crop to him. Just some usual everyday problems that a peasant faces in his life. Now the peasant has a magic sword. Turns out there was a massive battle on his farm 100 years ago, there were two armies, one of orcs and one led by a king, the king was the possessor of this sword, but in this battle the orcs were victorious, although they were later defeated in another battle. This battle occurred during a rainstorm, the fields were flooded, the King was slain by an arrow, and his sword went plop in the mud when he fell, further chaos in the field further buried the sword, the orcs never found it! The sword itself is a +5 sword. The +5 sword easily wins an ego contest with the farmer, it is not an evil aligned sword however, the farmer brings the sword home to his family, through the farmer's eyes, the sword assesses the situation. The sword is inert and unaware unless it is possessed by someone, that person doesn't need to be holding it all the time, but he does need to be close, say within 100 feet of it and so forth. The farmer is not aware he is being controlled by the sword, he just feels an urge to keep the sword relatively close, but the sword sees through the farmer's eyes and hears through his ears.
You know how the saying goes, when your a hammer, all problems look like nails. The sword is going to look for problems that the farmer has, which might be solved with a sword. Maybe for instance the Noble ruling the land is a bit oppressive, his taxes are a bit high, and he abuses his power a bit. The Sword takes note, does not like this situation and works on a way to improve it. The peasant is going to need some resources if he is going to overthrow this local lord. the peasant goes to a local tavern, hears rumors about some ancient ruins where there may be treasure. The sword convinces the peasant that maybe he should check this out, maybe get some other people involved as well. The peasant on his own would not ordinarily do this, which is what the ego contest is for. The sword tries hard not to get the peasant killed, so it makes a plan, convinces the peasant to look for some companions that would help it to complete its quest.