Aluminium; finishing touch

I like the looks of an unpainted aluminium hull very much. What i like less, are the ways they grind up hulls usually. I'm aiming at all those uncontrolled stripings, mostly horizontal along the hull. Sometimes the builder manages to do no grinding, or only at a minimum on the weld itself.

So i was wondering, is there no other way then grinding everything (after welding). Or some technique that can be done after grinding to create a clear finish (or more consistent finish). Sandblasting, or grinding in a circular motion crossed my mind

Example:

 

This is a photo of Steve Dashew's boat and I believe he has deliberately chosen to leave it looking low key. It looks like this was at launch time and over the next year, a patina will build up and it will all become a more uniform dull grey colour.

You can have the topsides buffed with a 3M's scotchbrite pad on an air DA sander. It leaves a completely round mark (125mm dia) and a skilled operator can quickly build up a succession of these 'twirls' that looks okay. (However, a bad operator can make it look shyte.)

 

According to Dashew's site, they left it like that because (a) low maintenance, and (b) looks less like an expensive yacht thus less attractive to pirates.
For examples of pretty aluminum finishes, give Duckworth a call. Some of their alloy riverboats are polished so smooth as to rival my bathroom mirror. http://www.duckworthboats.com/