1st gen tire size guidance

Hey y'all, I'm happy to be here and I hope you can forgive a foolish question from a newbie. I have done some fairly extensive searching prior to making this post but I'm seeking some direct guidance specific to my situation.

I have a 2000 SR5 4x4 5-speed manual 2.7L that I bought last year. It came with 31 x 10.5 x 15 Goodyear Wranglers on it, and a 265 x 75 on the spare. It's time for new tires and I'm trying to determine the best size to get. The inside of the driver's door mentions 225s, I had been assuming that's the original size for this truck, though I understand from a little research that some of them came with 265s/31s and I saw a thread about the door sticker being an unreliable indicator of the OEM size. The gear ratio appears to be 4:30 based on the OEM gear ratio post and the code on my door sticker. (RZN171L - CRMDKAB B07A)

This truck is now my daily driver, though I don't commute far and do a fair amount of off road driving. The 31s seem to work fine on the truck as-is, just occasional rubbing on the driver's side during sharp left turns, particularly with weight. It hasn't been lifted or re-geared to my knowledge yet. Is it stupid to have tires that large on this truck? It's slow but it does altitude fine (I live at 7000' and have driven this truck up to 11k) and doesn't seem sluggish except when I'm trying to go interstate speeds. I'd like to keep it as off-road capable as reasonably possible but I'm wondering if going with smaller tires would be the wise move. I'm also curious about recommendations for a reasonably priced 2-3" lift (I've read 5100s and shackles are the move?) Thanks in advance for taking the time.

 

31's sound like the size for you, nothing wrong with them.

the front part of your lift sounds great, I have no experience with shackle lifts