So this led to an argument and him telling me that she would have to get used to this anyway, because he wants 60/40 custody which would mean every other weekend and 2 overnights during the week. I have spoken to a few people who agree that kids should not be split up during the week. Coming from D'd parent's I totally see the importance in this and I believe in it deeply.
It is very difficult - Our D is really young, so we have a little more flexibility. In spite of all that is going on, we have NEVER disagreed about time we spend with D. We have our usual schedule (W - Mon/Tues; M - Wed/Thur; Alternate - Fri/Sat/Sun), but we have both been very creative with it at times. I had D extra days last week when W was sick, she had D an extra night or two a couple of weeks ago when I was sick, plus she had her Wed night too this week to make up for last week. That said, D has a room at both of our houses with toys and her bed in.
Honestly, I don't have a good answer. Part of me agrees with the consistency point, however I still think a more equal split of parenting responsibilities would avoid either of you feeling like you are getting more time with the kids than the other. Since your H is living with his Mom, it may not be a good time to attempt to figure this all out. I know my D would have a field day living with her grandparents, so it isn't really a long term 'reality'.
My W has brought up a few times difficulties she has had with D on her own. It's stressful to look after a child on your own (as you well know), and I have heard many complimentary comments from W about how I have handled my time with D and how much energy and time I have made for her.