I think Tyler is sometimes considered a bit downmarket in the UK, so I wouldn't use it personally.
If you go for a classic "grown up" name like Edward, Frederick, Alfred, Thomas, Samuel etc you could then use a cute nn for when they are little, like Teddy, Freddie, Alfie, Tommy, Sammy etc .
Alternatively what about Tristan, Dylan, Jared, Evan, Caleb, Owen, Ethan, Zack/Zachary, Felix, Rufus, Henry/Harry, Lucas, Max or Jack? - I think they suit all ages.