QAt the start of my end phase, if I have 6 remaining play points, can I draw a card before selecting a follower to destroy?

ANo. When an ability requires a selection, the selection must be made before you resolve the other effects in the written order. In this case, before you draw a card, you must select an enemy follower (you may also select no enemy followers).

QIf I have multiple cards with an "At the start of your end phase" ability triggering, in what order do I resolve them?

AYou can resolve them in any order. When you proceed to your end phase, all "At the start of your end phase" abilities are triggered and become pending. Then, you can choose the order in which you resolve the pending abilities.

QI have this follower and a Deux Ex Machina on my field, and I have 0 remaining play points. At the start of my end phase, can I choose to resolve Deus Ex Machina's "recover 4 play points" ability first so I have enough remaining play points to trigger this follower's "deal 2 damage to each enemy leader" and "draw a card" effects?

AYes, you can. Note that your remaining play points can't exceed your maximum play points.