Have a set of 19" Niche Milan wheels with Stance coil overs, need help stretching the tires. what size tires should I go with for a good aggressive look?

 

Do you need to stretch because your offsets are too aggressive or just like the look? For a safe setup I'd stick w/ a mild stretch like a 225/45 front 245/40 rear.

 

Since niche doesn't really make aggressive sizing/offsets it might look a bit odd to have a somewhat conservative wheel stance and trying to stretch the tires over them...if that makes sense.
As in, to make a 8.5 width wheel look "aggressive" via stretch you would need 215 or less since the stock 8in comes with a 225...that 1/2in doesn't do a whole lot
Just get some 245/40 and 285/35 and call it a day

 

that's what im running now. & it doesn't look good at all. Coil overs are at the highest position & rear end is rubbing. I did a little research what do you think about 235/35/19 or 245/35/19 with a 265/35/19 rear? The 285 is way too much tire.

 

I would go with what blnewt suggested. 225/45 front and 245/40 rear on those wheels would give you a nice slight stretch without having to worry about safety.