Cub we didn't do any classes at all and so far DD has made it to the grand old age of 22 months, and we didn't feel at any stage that we had missed out on anything.
WRT your birth plan - IMO any kind of plan that you are comfortable with is excellent, (whether that's no plan at all or a tome with a contents page and index) as long as you're prepared for the fact that any wishes you have may fall by the wayside depending on the circumstances. Unfortunately we can read the plan, the MWs can read the plan, birth partners can read the plan - but the baby doesn't get sight of it until it's too late, and even then they're usually too busy being angry at being ejected from their nice warm, comfy home to even look at it.
Ignore your Dad - you might have a stressy child, you could have the most relaxed baby in the world. Pot luck. If he keeps on, tell him that he's causing you to be stressed so if baby is a stresser, then it's his fault 
Your DH may feel very differently on the day, who knows? He may change his mind and then you decide that actually, he's in the bloody way and you send him out anyway. Do have have/want someone else to be with you? If he really doesn't want to be there, then don't force it. If he doesn't want to be there then you'll be aware of the stress and stress will hinder your progress.
How are we all this morning? Nothing interesting to report here. Which is good.