YANBU I can totally see where you're coming from. By him insisting on splitting it all half & half you are compromising on what is right for you (being with your child), but it's reasonable as its logical & shared parental input etc... But by him wanting to farm out your dc to a childminder changes the whole arrangement
He probably hasn't thought about it this way, but - hes basically saying that his need for more (more!) free time out weighs your need to be with your child, which is just wrong, both or nothing surely?
You are desperate to be with Ds, and he would rather give it away to a stranger than respecting your feelings and really strong primal need to be with your young.
You're not being over anxious etc btw! I had terrible torn feelings when I had to go back to work and had to leave my Ds half in nursery (nr my office that I wasn't actually keen on but was affordable), half with h. H hated it and whined the whole time (but didn't make any effort to get a job instead, lovely), and I felt like I was giving away an incredibly precious time in order to let others who didn't want to have the chance I desperately wanted! Compromised everything that shouldnt be compromised! Ds care and stability, my well being in so many ways - me & dc were both really torn and upset all the time...
Hated it & I lasted 6 mths before everything collapsed in on itself. Now I have no h (obv not something im suggesting for you!), and work part time & only some of that in the office, and have an amazing nanny who is great with him. I get more time with Ds, he gets better care when I'm not there, and for alot of the time when I'm working at home im around and have little moments with him through the day.... Soooo much better!