It sounds like you are doing wonderfully!
I absolutely see where you are coming from when you talk about restrictions feeling like cop-out safety nets. I've been wondering about this myself lately too.
Sometimes people follow the limited dates per week rule for practical reasons. Some people know that they get completely carried away with NRE and a more structured approach can help.
My GF, for example, gets wrapped up in herself when she's dating. She neglects her husband and daughter in terms of quality time and he becomes very unhappy as a consequence.
She makes time to date her new guy, but didn't consider making time with her husband until I pointed it out. For her, having a dating structure helps her remember to make time for that existing relationship. Sometimes declaring love and commitment isn't enough - you have to balance the time, too.
Our general guideline (not a hard rule) is to date secondary partners once a week. Our new guideline is to try to ensure that primary partners get that same amount of time per week.
There's another reason we have this guideline... and that is to do with long-term goals.
I live in the UK and my GF lives in the US with her husband. Originally, I wanted a second primary partner in the UK. I was happy to consider living with them half the time and my GF half the time. Because of that, we had no restrictions on dating schedules. My GF was in love with me, her husband and another guy. We were both very open to the idea of loving others and I fell in love with someone else too.
These days, our relationship has evolved. We want to live together permanently, as a V, with their/our daughter. I don't want another primary partner. I don't have the time or desire. We don't want another else to move in; largely due to our daughter. My GF says that she doesn't have the desire either.
Seeing other partners less isn't going to stop us falling in love with them. But it helps to keep things casual. We also pick people who want casual - especially those who already have other primary partners.
So, how do you feel about this? Are you quite flexible about the future? Do you have children to consider? If you're very open about the future, then being fluid about dating schedules might be a great idea!
As for letting go of the fear... I find the best way is to just live through the experiences. If Captain falls in love with another and you are still very happy, your fear will naturally dissipate with experience.
me: female, 29
GF: my primary girlfriend, 39
3 year, open poly V, long distance