Great, olderndirt, sounds like you're 'getting there' fast now.
A few specific tips.
About control sensitivity, I'd recommend that you largely stick to the default settings - Easy, Medium, or Hard. The reason being that 'monkeyed' settings may suit one aeroplane, but not another. Way back when I started I used 'Easy' but soon moved on to 'Medium,' and then all the way to 'Hard.' The reason being that, set to 'Easy,' the control responses were just plain too late, and too 'soggy'; like stirring a pudding!
I expect that your instructor told you once, as mine did, that it's 'eye/hand' coordination, not the other way around - your eye tells you how much response you're getting and THEN you tell your hand how much or how little to move the stick. As he put it. "Sooner or later you're going to HAVE to learn to look THROUGH the windscreen, not AT it!"
About 'Shift-Enter,' pressing the spacebar returns the panel to 'default.' As part of my approach checks, I usually 'zero' the panel position and then add one or two notches, whatever suits that particualr aeroplane.
Not much more to be said about the rudder, since the one thing that FS can't impart is 'seat of the pants' feel. You can't feel a skid or sideslip, as you can in the real thing; so you have to pay close attention to the 'visual clues.' Best to use the rudder as little as you can early on, bsnking is usually enough to keep lined up.
About taxiing, try starting a flight from 'parked,' and practise taxiing from there; you'll soon get the feel of the rudder for that partuclar aeroplane that way. After landing, always best, IMO, to slow to walking pace at first, then feed power on gradually to taxi. One thing about FS, even if some poor bugger behind you DOES get told to go around, you don't have to apologise to him in the bar afterwards!
One thing we haven't mentioned yet - trim. The normal key assignments are 'Num 1' and 'num 7' - which is awkward, as you basically have to look down at the keyboard to adjust the trim. Instead, try going into 'Assignments,' and scrolling down to 'Elevator Trim Up'. Click on 'Change Assignment' and press a button on your joystick (I use one at the top of my joystick, right under my thumb). Press OK and that button will then control 'trim up'; then do the same with 'Trim Down', assigning another button to that.
Then you'll be able to adjust trim without taking your eye off the important things. If you get it wrong at first, just click on 'reset defaults' and try again.
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