Surprised nobody mentioned to the OP that Henrik has mentioned he might do an NA server as a separate continent later down the line.
But the OP's response and staunch resistance that without an NA server he's not going to play is something they had better be prepared to overcome. Just saying, "We've tested it, it's fine" is not enough. As he mentioned, they at least need a technical explanation of why it's fine.
I remember For Honor having to explain like crazy with how their peer-to-peer tech would work fine, and got ENDLESS flak for it, so they eventually just had to cave and go to dedicated servers. If you do anything other than the norm people expect, the burden of proof if on you to prove "it's fine".