Offset for flush fit

Sup Guys, had to re-post cause I posted it in the wrong section..

Hi Everyone, long time reader first time poster. Truly appreciate the wealth of knowledge and you guys willing to share it here!

I've got a 98 extra cab 5 lug that's all stock. Well, it had an AAL kit which gave it that wack (but functional) stance. With what I found here was able to safely take that thing out so now my truck looks normal.

I'm coming from a 1992 standard toyota pickup which was great, but man this thing rolls like a lexus...not really but waaay better than 92.

My question is, what is the widest tire/wheel setup for most likely some 15" wheels running 55 or 60 series tires. I don't want to give up too much ride quality for minimum performance gains. I also want to keep the rim/tire flush with the body. I'd be open to 16" with lower profile tires, but not much more than that since my pickup is a 4 banger meant for some decent gas mileage.

I may look at a mild drop in the future, but $$$ talks.

Thanks in advance!!!!

-Steve