I worked very little at the beginning of NP school, and basically quit work about a semester into school. Thankfully I had the financial means to do so, as it sounds like you do. As far as losing skills, well I guess I did, at least some. I had been working ICU, and I didn't care if I lost some of those skills, as I didn't plan on working in that setting again. You won't forget the essential skills, they are part of you by now, but taking care of a vented patient isn't among my duties now, so it was fine with me. Additionally, just by chance, I got a PRN charge nurse job at a LTAC about half way thru school, which I am still employed PRN. I haven't quit there even though my job is now in primary care, but I like the PRN position and the other employees too. Some may disagree, but I recommend not working while in school, if able.
I truly respect those that can work alot while in school, but I chose to just focus on school and family. I don't regret it one bit either, and no one ever questioned why I didn't also work. It's clearly listed on my CV when I left my job, but school filled the gap.