sounds like you are just looking for someone to tell you it's ok to buy what you really want, even thought it costs more and adds marginal utility.
Do what you want, it's your money.
The vibe & coolness factor exists almost exclusively on internet forums. When you are in the middle of nowhere riding your loaded bike, it doesn't matter even a little bit. In fact, the less you care about the bike, the better, because it's going to fall over, be thrown and dropped by the baggage monkeys at the airport, get rained on, covered in mud, shat on by birds, covered in pine sap, etc. etc.
I've run Continental TravelContact 35's on my 520, w/fenders. I like the bar-end shifting. I swapped for mountain bike cranks, ditched the stock rack, saddle and pedals.
Good luck w/ your decision, and have fun on your tour!