capthaltli, to answer your question about line up during approach. There is no 'drifting' (gradually coming back to centreline to be there at the ramp for example). As has been said 'meatball, line up and airspeed (Opt. AoA)'. There is no other (HUD for part of the way I would suggest is used by experienced pilots rather than newbies as I understand). Technique is to be on or getting very quickly to the three parameters.
The angle deck is moving forwards and because of the angle the angle deck is moving to the right of any aircraft lined up - all the time. Necessarily to stay on centreline the aircraft has to 'nibble' (make small wing downs) to the right all the time. Keep all the parameters as close to ideal as possible all the time. If out of alignment then get back ASAP and stay there. Yes I know easier said than done but that is carrier aviation.
ADDITION: Also 'crossing the wake' is important before lining up on centreline of angle deck (see illustration attached)
The reason for 'no drifting' is that if you can manage to use this land based airforce technique then you will be at the ramp with the nose of the aircraft not pointing down the angle deck. The LSO will have waved you off anyway but if you do arrest it is likely you have a bad off centre arrest causing perhaps problems for your aircraft and others.
Yes 15-20 seconds in groove is ideal AFAIK. Probably the shorter the better.
If and when F-35C automatic landings become standard during the day then JPALS would have to be in use (not available yet) and it would need to be done from this kind of day circuit most likely unless somehow a long straight in approach with successive aircraft being close together is devised, using the precision of JPALS. Having short time landing intervals is critical during the day to get aircraft aboard expeditiously so that the carrier can do other things off the BRC or whatever.