Join Date: Oct 2013
Location: Thessaloniki, Greece
In my opinion, a bike used mostly for commuting, short or long trips or more than occasional highway use should keep the factory pipes. And that's coming from a guy who has done 800 mile days on a naked bike with a straight pipe on.
The quietest solution other than that would be a buff slip-on approved for road use, and thus compliant with noise/emission regulations, and so probably made by an eponymous company.
In your case, by experience, I can see many drawbacks. You care about your neighbors, you want smooth highway cruising, it seems that an aftermarket exhaust is just not your thing and will cause more anxiety than joy. By the way, the repacking procedure is periodically required by some exhaust manufacturers in order to keep the can in working condition, it's not meant to reduce noise levels.
So, if the factory pipes are not available, I would recommend the quietest, road legal slip-on you can find. And as always, in any case the golden rule is to choose a bike specific, eponymous product developed and tested for your specific model of motorcycle.