As our (now-teenage) twin sons got older, my ex wanted to move from EOW and 1 evening/week, to 2 evenings/week, ostensibly so he could be more involved in extracurriculars and helping with homework. In general, he seems to feel more comfortable/competent/interested in the work of parenting older kids, compared to, say, toddlers.
I hated to spend *less* time with them, while they were already spending less time at home with parents anyway, and getting ever closer to being adults living on their own. However, I tried to focus on their need for more time with their Dad as they approached manhood; the fact that it's better for any kid to have both parents involved with school, sports, etc.; and that I'd been lucky to have so much of their time while they were younger and it was fair for my ex to want more.
But old habits die hard and the 2nd weekday evening never really took off. My ex kept having to miss it, for various reasons. He felt guilty cancelling, so he'd tell me at the last minute or just not show up. Rather than fight about it, I carefully suggested we switch from assuming he'd have the kids that night unless he said otherwise, to assuming they'd be with me unless he told me in advance he was going to exercise "his" 2nd night. So, he wasn't technically giving it up, just dumping the expectation that he call me to cancel. Since then, he almost never has time for the 2nd night.
Lesson: flexibility is the absolute key, for older kids. Their commitments and interests deserve to be a higher priority than a rigid schedule meant to accommodate their parents, whose divorce and separate lives were not the kids' decision. If your ex wants - and is able - to do more driving to practices and lessons, and more homework nights, you should let him. But the most important thing is that the kids get where they need to go, regardless whose parenting time it's "supposed" to be. Same with weekends. It's one thing for courts to set rules that one parent may not schedule play-dates for a 5-y-o during the other parent's time. It's not fair to set limits like that, for kids old enough to start scheduling their own social lives. If a kid wants to go to the movies with his friends on Saturday - and there's no reason he shouldn't be allowed to go - both parents should collaborate to facilitate it, regardless "whose" weekend it's supposed to be.