It sounds like you want to end up at an airline. If so, I would lean towards the Cape Air gig. If you are unhappy flight instructing, is it because of the company or because you don't like giving instruction? if the latter I advise you get out as soon as possible. Being an unhappy flight instructor is not conducive to giving good instruction. Leave while your integrity and record is intact. 20 years from now you can look back at your time as an instructor and feel good about the job you did. Also, the other two options will give you some good Wx experience and with Cape, more multi-engine. You will appreciate both of those as a Regional new-hire.
Also consider what your spouse does for a living. Can you survive without his/her income? If so, you can move to wherever you decide is appropriate and commute if necessary. If you are at Cape Air you can commute, but you will lose some days off each month doing so. If you go with Planesense, you will not be able to use an airline jumpseat to commute and will need to live where they have a base (unless they airline you to where the airplane is).
Basically I would say it depends on your situation at home and whether you need to commute or not.