It doesn't sound like you need advice on the subject (sounds like you and your ex are coordinating just fine about the younger son), but if you're just taking a survey...
My ex and I get along very well, but part of the reason may be that we don't try to coordinate doing things the same way at our two homes. We're both strong-willed and have different takes on when our kids should wake up/go to bed, what they should/shouldn't eat, what is/isn't appropriate for them to watch/play/read, what chores they should have, etc. So we keep the peace by respecting each other's right to set the tone in our own home and only trying to insist on sameness when there's a really serious concern. One could argue that it's harder on the kids not to have perfect consistency. But it's a broken, doubly-remarried family. No amount of consistency is going to make our kids "forget" that their parents keep completely separate homes. On the other hand, the more peace, respect and good will my ex and I learn to extend toward each other, the more we minimize stress and anxiety for the kids, given the imperfect reality of the situation.
Our kids know if they want to stay up late on weekends, they need to bank on doing it when they're with me, but if they want to watch Zombie Land, it'll have to be at their Dad's. But they also know that if I say something is so completely unacceptable that they can't do it no matter where they are, their Dad expects them to be honest and not try to weasel him into giving permission in spite of me - and vice versa!
On the opposite spectrum, my husband's ex used her "consistent schedule" for their son as a way to marginalize my husband: Instead of letting my DH pick him up from school on his visitation days, she made the kid spend 1.5 hours on the bus and "transitioning" at her house, because that was his "routine". Even in 2nd grade, she insisted DH's weekday visits end at 7pm, because she claimed their son had the same bedtime he had in preschool and needed time for his "nightly routine" at her house. When she moved across the country, one of the weeks my husband flew out to visit, she refused him ANY weekday contact because their son had standardized testing and she wanted no deviation from his usual schedule (which - by her design - no longer included DH, but DID include some 13 hours of after-school care...)
SO, there was no coordination with his ex - it was too difficult just trying to coordinate BIG things, like exercising his court-ordered visits. And there was no way to know whether she was honest about things like bedtime, or whether she just said what was most convenient to limiting DH's visitation. That's how she is. Now that their son lives with us, he sees so little of his mom and she's so resentful of DH getting custody that DH tries to set as few parameters as possible for her parenting time, when she does visit. Anyway, when DSS flies out to see her, or she comes here and he stays with her in a hotel for a week (twice a year), it's such a big upheaval for him that I can't see how details like keeping the same bedtime would really matter.