my F54 came with 16" Rims. im trying to switch it up, what is a good size not to make the ride too rough..? any suggestions of what will look nice?

Thanks)

In my opinion, the F54 needs at least 18-inch wheels. I wouldn't go smaller than 17, though.

Look to get the lightest wheels you can afford, preferably flow-formed for rim strength.

I would likely stick with bumping up to 17's, so you can keep enough side wall on the tire, since you are concerned with ride quality. I agree that 18's would be a better 'look' on our cars, but you end up with pretty short side walls on an 18" and that will increase the ride shock quite a bit over your current 16's. What will look nice...beauty is in the eye of the beholder/owner. I don't have much aftermarket wheel experience, but my TSW Nurburgring wheels on my 'toy' have held up very well to 10 years of road trips, auto-x and track days w/o any issues. That style would also look good on our cars...if they offer a correct size/offset. TSW has one of the wider ranges of wheels and fitments for reasonable prices. Good luck on your project.

You have to go 18's or 19's as 17's look way too small and the side wall is too high and cornering is too squishy. I have been running some 18 inch Work Wheels and find the ride comfortable. That being said I think I am going to sell those and go up to 19's as I seem to prefer a lower profile sidewall considering my driving style.

18' it is )

only cost me $150 with almost brand new Tires!

For that price, it was a deal you couldn't pass up! While I like the size of the rim, those sidewalls just seem a bit too small for the car...but that is just my view/opinion.