I definitely prefer the name Ian due to it’s sound. It’s also not very common where I am, either. So, I do like it! Rhys is also a very nice name, but I kind of prefer the Reece and Reese spellings.
Apparently some people pronounce, or have pronounced, Ian to rhyme with Brian, so anything is possible.I like both, but Rhys has no personal associations for me so I would definitely use Ian, to honour two dear friends and an ex-BIL.