Wei Minghan (Taken from Mingbu Jinghan, meaning: Having a bright future and a broad mind.)
Wei Xiaoran (Meaning: Natural, refined, unrestrained and generous.)
Wei Yuze (favors as abundant as rain)
Wei Haoyu (mind as vast as the universe)
Wei Hongtao (Hong: vigorous, prosperous)
It's grand enough and has the word "water" next to it, which is very poetic. If the boss can't do it, I will break my head if you are more specific. Also help your son find a resounding name