which would be best ... for 18x9.5

[Majestic400]

i got a ls400 with 18x9.5 and 18x10.5 ssr vienna's what i really wanna know is that ls400 is a heavy car.. and on my z i usually stretch 10.5 with 235/35 and 11.5 i stretch on 245/35/19
but that a z which is a sport car with no back seat .. but for my ls400 i will be driving with full house all the time.. .and i was just wondering 215/35/ is good for 9.5 or 225/35/ will be... and on 10.5 i will be stretching 235/35/18 ... so anyone recommended ?