Yeah that's the problem I saw with the ACNP... you pretty much will work in the hospital setting and you will work what the standard schedule is for the NPs. At my hospital it is 5 on and 5 off, so definitely some weekends, but not all. They also do not take any call, which is a plus. I went thru this decision process as well and have decided on getting the FNP, more marketable overall as well as the most likely to get me a job with normal hours, no holidays, no weekends, etc. I am tired of missing every other Christmas and Thanksgiving and every other holiday.
I want to enjoy my kids and be there for all their stuff.
As far as your schedule and clinical, I think working the weekends is excellent! That gives you all week to get your clinical experience, not that this matters if you are doing clinicals in a hospital setting, but it definitely matters when you do clinicals in a clinic setting that is not open on the weekends. I work every Mon, Tue, Fri (used to work weekends and wish I had that spot back for school reasons) and I will more than likely cut down to PRN during clinical so I can get my hours in as I will need those weekdays to do it!
Good Luck with your decision. Just decide what's most important to you NOW. If you want more family time and flexibility, go FNP. You can always go back and get a post master's in the ACNP later on down the road when your kids are a bit bigger. They are only young once!