Well lets look at this in pros's and cons.
Here is the pros's for each man you listed:
Mature and responsible
Do not have to move
Cheater (And since it was your sister this should count as 10 points!)
You can not let go of the past
Not responsible (If he was he would have a job)
Love can do a lot, but it isn't a miracle cure all.........the reality is while you may have once loved this old boyfriend the reality is it ended for a very good reason. Any man that would degrade himself so low as to sleep with his girlfriends sister isn't a man. I am not saying a man does not make mistakes, we all have been there before and even a man who cheats can change.....but a man who cheats with his girlfriends wife is lower then low and cared so little for you that he did not even offer you this compassion.
He does not have a job.....which is another huge issue. While yes a man who has lost his job isn't a immediate no no, the question is why isn't he in a more secure job? Does he lose work frequently, or simply not work? If so this is a big glaring sign of his worth as a man. A man who can not, or will not keep a job isn't responsible enough to be in a relationship.
The fact is getting over infidelity to begin with is hard.....but adding that he did this with your sister and its going to take a lot of work for you to forgive him. And the reality is if he cared so little about your feelings to cheat with your sister, then you have to question wither he would cheat again.....and with anyone.
You have a man who obviously cares for you, is response, mature and faithful. The move may seem scary.......but whats scarier, trusting a man who cheated with your sister or moving 200 miles away?
Of course I can not make this choice for you, only you know deep down what you want. Just make sure you do not trade a good secure happy life for one where you will end up miserable over something so small as a move.
Thank you for the additional information...........your original question painted him in a different light
As for your sister, of course this was not cheating, but it is something that may cause some conflict for you so it is something you will need to consider. The reality is you were 16 when you loved him, or cared for him. You both have grown and changed over the years and what you once felt is not going to be anywhere near how you feel right now. Of course, you could find that spark and live happily ever after......the problem is you do not want to lose what you already have on a "maybe"
The reality is it sounds like you have everything you need in your current boyfriend, of course the move is going to cause some anxiety but at the end of the day if he is everything you want and need then do not allow a move to cause you to question your feelings for him. Often what we think of as "Our type" typically is the wrong type. You can find a type of man you are attracted to every day......but that does not make him the kind of man who you can settle down with and make a good life with.
Of course your old boyfriend, is your type.......but then again your type has typically lead you into bad relationships in the past as you mentioned above. This new boyfriend isn't your normal type, and everything you want and need in a man. Which would be wonderful for you.
As I said above, I can not make this choice for you. But the reality is you have a good thing already, and chancing it on something you had 30 years ago is a big risk.