That’s because what you’re getting back includes collections of objects, and when turning those into text PowerShell can only display so many, so it adds the … at the end to indicate it ran out of room. Your problem is that you’ve got one property which is just a single value, and another property which is the collection. Since Format-Table has a limited amount of intelligence for dealing with that, you need to take it out of the equation.
Two, the braces are caused by the fact that proxyAddresses is a multivalued field. There are several ways to deal with this.
Get-ADUser #...# | Select-Object SamAccountName,@{'Name'='addresses';'Expression'={$_.ProxyAddresses -join ','}} | FT #...
That way joins the proxyaddresses with a comma.
Just as an aside, I might consider just using Export-Csv instead of the column width thing. That’s a good format and Excel a good tool for viewing the tabular data.