I would argue that 17"x8 or 9 is the best rim size, especially for offroading as you can lower the tyre pressue a lot more and lay down more surface area for extra traction. 17in tyres are cheaper and more available in most countries and are far more comfortable on road than larger rim sizes.
I very agree with you to use back original size tyre and 18" size rims, just get wider jj rims then its good to go. Fuel consumption also save. Good recommendation.👍👍👍
From what i see on lenzo zeus 03, if u go for 9jj rims, offset +10 is nice and aligned with fender. Offset 0 also would be good. But would be different if u using 8.5jj and 9.5jj. Let say ur 9jj +10 aligned with fender, then 8.5jj u need offset +5 to aligned with fender. U need to + some and - some with different jj.
positive offset will tuck inside from the fender but not much since the rim jj is quite wide. i use 18x9 et0 and the rim itself is already tuck outside abit so even if u use standard size tyre it will tuck out like about 1-1.5 inch out from fender. my 2.8 fortuner need to lift up my front at least 1 inch to accommodate the wider tyres
