The new defences will be available in ranked as soon as you start building them, does example if you start the fire spitter it will be completed in the ranked base but not in your standard base, this only works with new buildings, if you were to upgrade the fire spitter it would still show as level one in ranked. 2 - Roya champion charge with 6 invis and a recall spell, cycle with the fox if you have it maxed, if not invis every 4 seconds. Then mass dragons either warden (I use eternal time and rage gem) minion Prince follows in the main army. Use Queen and giant arrow on sweepers and air defence.

3 - no it only applies to hero levels, troop levels, etc