I think there are a plethora of ways Allomancy and Feruchemy could be used in peaceful applications. I've even thought about it in some depth once or twice myself, but I'm generally attracted to Allomancy, so most of my ideas use Allomantic procedures.
For example, the flight issue. To me, this wouldn't be hard at all with a hang glider. Simply steelpush yourself up into the air, open your kite-like device, and use it and the wind to propell you to your destination. If you lose too much height or need to change direction, simply toss down a few coins and you have renewed momentum. (This could be especially useful for crossing the deserts at the edge of The Final Empire, as the desert heat would provide plenty of updrafts.) It seems a convenient way to travel with minimal steel/iron usage.
Another helpful aspect of Allomancy would be the capability to twirl metal segments. (a la Kell in his Inquisitor battle.) Using this concept and a couple of Allomancers, generating electricity would be relatively simple. Just set up an energy efficient turbine and have a Mistborn come by every morning to duralumin push/pull it into continued production each day.
Medical science could be vastly improved as well, as with an Inquisitor's vision (A learnable ability by any lurcher/coinshot) doctors could quickly and easily identify any number of problems in patient's bloodstream/mineral levels/etc. Diagnostics would be quick and painless, and the surgeons could "see" exactly what was happening in real time.
Teaching and academics would benefit greatly from a few soothers, in my opinion. A whole class could be brought to an attentive and knowledge-seeking attitude with the help of some brass. Small children would especially benefit from this, I think. On top of that, physics principles such as the Newtonian laws could be taught by example much more efficiently.
Psychology would see an improvement, as gold and malatium burners could identify pivotal moments in a subjects life while emotional Allomancers guided a patient's moods. A few mental diseases could possibly be fixed with some duralumin soothing and rioting.
Atium and electrum would cause some very interesting effects, especially when combined with duralumin. As an example, military tactics would probably rely less on outguessing the opponent and more on deducing what they were doing from their atium and your electrum shadows. Important figures could know ahead of time if someone was attempting to assassinate them, and even the average electrum burner could tell if they were going to trip down the stairs or stub their toe.
With all of these wonderful advances, I think the largest problems would be economic. Metal prices would shoot way up, and the only reliable way I know of to replenish them would be the Well of Ascension. So every thousand or so years, the "Terris" people, (Or whomever controlled the Well.) would have to be able to produce enough metals for the next thousand years in one go. (And probably also create enough of the Mistborn-making metals to ensure society had enough specialists.)
So those are just some of my ideas, but it's getting late and I should go to bed. You guys have any good ideas?