Can I ask you how many DCs you already have, fideline?
Sometimes these situations come about because new relationships evolve, and that couple want a child together....it's hard to say without a bit more info, tbh, as each family's circumstances are different.
My DD finds it quite hard to revise with a houseful of young siblings making a racket, but she is quite happy to revise at her grandparents' or at college.
I do feel that in some respects my DD1 missed out, as a lot of my time was taken up with babies/toddlers. Years of sleep deprivation left me pretty knackered, which she was aware of, as she was old enough to notice.
If all your DCs are tucked up in bed by 7:00pm, and you haven't slept the night before so want to go to bed at 7:30pm, it doesn't matter, but if you've got a teenager wanting to talk about something and you can barely keep your eyes open, it's a bit
.
This happened to us quite a bit, but then I had 3 children in fairly close succession. If you just had one, it would be over and done with quite quickly.
Holidays are tricky - trying to find something that fits in with toddlers and young children and older teenagers is quite challenging, but not impossible.
I've read lots of positives on here from people with big age gaps before.
Any chance of a bit more info, OP?