Contrary to common thinking, those bulbs do NOT require relays; both the bulkhead connector, and the headlamp switch, will handle them no problem, at least in the North America, and with sub 200amp alternators. Just make sure the grounds are good.
As for the direction of filament winding, I agree that they are self correcting/adjusting, but if if you're not careful, and happen to kink the wire, they occasionally oscillate. Since there is no visible evidence of this,it would seem not to be important. But, you have to make sure that this phenomenon, does not feed back into the headlamp wiring, because it is not well understood by science, and there is no known cure for the hairloss that can result from this.
It has been suggested that diodes can be used to eliminate this oscillation,but fitting them to each bulb under the dash is rather tedious. The usual work-around is to just fit one large diode on the input cable. Unfortunately, the V8starter has a nasty habit of rupturing it, so this requires some creative re-wiring, because a diode robust enough to cope with the current draw, is rather large and heavy. Most lighting experts agree that such a diode would make those bulbs rather a PITA to employ. Consequently, the individual diodes are still the best choice. However, the simplest solution seems to be, to just not kink the wires during the winding process. To that end, the industry has more or less taken the process over, and few mechanics still wind their own. And besides that, the forming and sealing of the protective glass envelope is rather time consuming, and success was often hit and miss, so most mechanics polled said they were glad to be relieved of this somewhat tedious chore. And finally,the mass-produced bulbs seemed to have a higher success rate in avoiding the dreaded oscillation phenomenon.. Another side effect of mass production, seems to be that it has lead to longer filament life, and less frequent removal of the instrument clusters, a welcome thing indeed.