It looks to me like you are answering your own questions.
As to the question whether you should go for PR or work permit or both, it depends on your options.
Do you qualify to apply for PR from outside Canada? If you do, you can do that.
Do you have a job offer / LMO that will allow you to apply for a work permit? If you do, you can do that.
If you have both options, if you want to get to Canada faster, you can go for the work permit and apply for PR at the same time or later. If it doesn't matter to you, you can just apply for the PR and wait.
One downside of being on a work permit is that you are more or less stuck with that employer. If it turns out they are not very nice or they are having a hard time and have to lay you off, it's not so easy to change because you will need a new LMO and a new work permit.