First, congrats on your engagement!
One of the great challenges faced as a parent is to grow with your kids, into a healthy happy mature adult relationship. As a mum to a 14yo son and 17yo daughter, I'm blessed to be experiencing this aspect. Their father on the other hand is a slightly different story. I watch him act out the role of his father - He's raising them and has supported them for years therefor should be automatically respected as their father. He's more of a passive guy than a tyrant. And, yes, he sulks a little when there's a lack of co-operation, occasionally announcing how disrespected he feels. The sad part is - whilst his kids love him, they don't have a huge amount of respect for him, especially my daughter. She can't respect someone who doesn't respect her or even try to understand her as a person.
I believe the role of a parent and their child is - mutual supporter and guide. Whilst I raise my kids, they also continue to raise me. This is how we've grown together so easily; we support and guide each other. I suppose, at the end of the day, the appointed roles really need to be clear and mutually agreed upon, otherwise there is going to be disappointment on a variety of levels.
Sometimes a parent will need to carefully guided toward change. Now, I know this is going to sound terrible to some people but the advice I occasionally give my daughter is 'You need to manipulate your father's way of thinking if you wish to have him see things from your point of view'. Manipulation is not always a bad thing. It may simply mean helping another person gradually change an outdated destructive belief system that serves no real purpose'. In this way, manipulation reflects the skill of reasoning.
If you wish to manipulate your dad's way of thinking, try reasoning with him in ways he can relate to. For example, instead of proclaiming how much time you believe you should be able to spend with your partner, ask your dad about the early days in his relationship with your mum - how much he loved her, what he did for her back then, how much they were devoted to each other etc. Invoke the emotional side of him that can relate to the excitement in the early years of romance. Guide him back to a time where he can relate.The strongest relationships are the ones where people can best relate to each other.
We won't always achieve 100% success when it comes to what we want; sometimes compromise is the middle ground where mutual respect is born.