>I don't think the plan was to BLOW UP Gotham originally, so I
>get the whole plan to destroy Bruce for turning his back on
>the League and taking his wealth as well as making him suffer
>etc.

I thought Ra's plan was to destroy Gotham and then rebuild.
The first scene was getting the guy who could make the bomb. Working with the other financier was aimed at getting Talia control of Wayne Industries so she could get the fusion generator. Bane says fairly early that he knows the thing is going to blow up in five months regardless. Blowing up Gotham was always the plan; making Batman suffer was an added bonus for Talia.

>I am engineering major, but, why didn't Bruce or anyone in the
>prison use the rope to just climb the fuck out.

The rope only seemed to go halfway up, to the point where you have to make the jump. Climbing the rope would still only get you that far (and not to the ledge you need to be on to jump, I believe.)