May i point out that you guys are mostly looking at battle strength and such to call her weak... i think that depending on what kind of bankai she would get should decide if she should get one... i mean squad 4's captain isnt particularly strong but her bankai is rather cool and suited to her... if rukia were to get a bankai... i think it would need to be along the lines of a support or non fighting bankai... maybe something even like issen's bankai (though i think i just spelled his name wrong...)