I'm glad you used metacommunication to warn us it was a rant.
Great skill that is actually!
I didnt read the whole post-I read enough to come to my first conclusion (I do tend to read some, then go back and read more).
FIRST AND FOREMOST-
POLY IS NEVER NEVER NEVER NEVER an acceptable addition to an already rocky and screwed up relationship.
it's not fair to the people IN the relationship
it's not fair to the people who would be added
it's not fair to the family (in your case-kids)
NO IT IS NOT ACCEPTABLE at this time to consider a poly-dynamic REGARDLESS of where this person lives.
Therefore-there is NOTHING on that topic to discuss today.
FIRST you two need to repair your own relationship.
YOU need to stop allowing yourself to be taken advantage of.
HE needs to take responsibility for his share of the kids and housework.
Having a job does NOT reduce ANY of the responsibility he has as a father. A paycheck DOES NOT build a relationship.
If he's gone for work 10 hours a day (I allowed for drivetime of one hour each way)-
there are still 14 hours in a day which need to be spent attending to children needs. OBVIOUSLY they are asleep for some of that-which is great. Lets say of that 14 hours they are asleep 8 (you can figure out precisely how much it is), that would leave 6 hours-and 3 of those are HIS RESPONSIBILITY.
You can break it up by he does feeding/meal making every other day and he does bathtime and bedroom clean up (toys/books etc) with them every other day. He can do bedtime routine every other night too.
These things are what create a familial bond and it's not only his JOB it's also his GIFT to himself and the child.
Don't short change your kids by allowing that to continue to go unchecked.
We had issues with the "I worked all day" followed by computer vegging out too (we have 4 kids).
Flat out-no joke-time to go AA style and give up the video games and tv. He needs to get out of that addictive pattern and start focusing on his REAL LIFE instead of the imaginary life in those electronics.
If he's bored-it's because he's not doing his share of the work-if he was, he'd be exhausted.
SECOND piece of advice-no parent is a great parent if they don't take a break. YOU NEED TO SCHEDULE a break EVERY DAY for yourself.
He checks in for parenting duty and you check out.
Go for a walk-go take a bath-go read a book-go have a coffee-go shave your legs-go do something NOT MOMMY ORIENTED.
THIRD-you two need time to negotiate. So, tell him that for the next month-the topic of poly is OFF THE TABLE and explain in concrete (not abstract) form what 5 things you need him to do CONSISTENTLY for the next month and list out 5 things you will do CONSISTENTLY for the next month to better YOUR relationship.
Reiterate that YOUR RELATIONSHIP is having ISSUES and until THAT has been resolved-the option for DOING poly isn't there.
But, that you will re-address the TOPIC of poly in 1 month.
At that time-you address what has been going well, what still needs work and you each add 5 things to the list of what you need to do/change for your relationship.
Continue until your relationship is healthy and happy for both of you and the kids.
THEN you discuss the options of DOING poly (or if its not an option-whatever)