Maybe you should have an "accuracy" aspect be an aspect of weapons or objects? You could have an abstract "weight" score that demonstrates an object's generic weight and hand-ability. So, if a weapon lists an accuracy use that (as a modifier to the attack) OR if not, then use the objects "weight" score as a penalty to the attack. I would always keep "talents" and "skill" and other such factors on the character side of things versus the item\weapon side of things (so if a character is good at brawling, they have an "ability" or "talent" that improves their attack with improvised weapons, as an example versus trying to weigh in that factor in the broken beer bottle stats).
I would need to see more of you base system mechanics to help with impacts on numbers. The art of creating a character creation process that favors concept over optimization is obscure at best. There are a plethora of methods from simple "GM approves everything" to "combat stuff costs 3x as much as non-combat stuff" to "you can spend COOL POINTS if it has something to do with your goals, motivations, or flaws". YMMV.
It would be great to see a summary of your system basics, give us a better context for the discussion.