hi guys , planning to change to my stock rim and tyres (205/55R16) to R18. did some research/calculation and it recommended me to go for options below if want to have same comfort as previous one.

http://www.carbibles.com/tyre_bible_pg4.html#slr.

New spec            %diff
125/70R18  0.13
215/40R18  -1.20
225/40R18  2.35
245/35R18  -1.42
255/35R18  1.69
285/30R18  -1.64
295/30R18  1.02
305/30R18  3.68

Im thinking of choosing option 225/40R18 , but wondering if i can expand the diameter a bit to 225/"45"R18 to make look just nice fit with the fender. plus im also wondering if 225 is a good tyre width not to exceed the bodyframe (im not a fan of tyres looking popped out from the side body)

any sifus experienced using 18 inch wheel are welcome to advise.