We're in a bit of a different boat remodeling our 1970s pool, but we lived with it for two years to identify what we really wanted to change so it's kind of like we already got a "do-over!" We're in progress, so none of these have shown to pan out yet, but here's my two cents...
Some things about our pool that we are remediating in the renovation:
1. drainage, drainage, drainage. Our yard is on a bit of a slope with the pool in a flat area, and the yard uphill from the pool would flood over the retaining wall in heavy rains and washout the pool with dirt and leaves, screwing up the chemistry and killing our swimming for a week or two each time while we got it cleared again.
2. auto-fill. I know these are somewhat controversial (you could be topping off a huge leak and not know until your massive water bill hits) but ours will be buried right up to the house's hose bibb and attached visibly there, so we can turn it off and on as needed/winterize. I hated having a hose run across the deck all the time, would forget to turn it off until the middle of the night, etc. Looking forward to this.
3. good clearance all the way around the pool for cleaning access. Brushing your pool is essential and having to scramble up on the retaining wall (ours was bumped up to the pool's coping, so only 12 inch walkway) was a major pain with the pitted/worn rock wall, and I almost fell in/twisted my ankle several times. Our new wall is pushed back 3-4 feet from pool edge
4. shade! I love the pool but I burn like crazy, so I slather on sunscreen and have to spend a lot of time in the shade. We're including lots of in-deck umbrella sleeves with covers and building a pergola at one end of the pool for a more permanent shade structure (and more wind-proof here in OK ... there's lots of times it isn't feasible to use the umbrella).
5. warm water! We're choosing a dark finish to try to warm up our water. I hate cold water, and like to ease into the pool warm-bathtub style. We're starting with a dark finish, and if that doesn't work, we'll look into adding some solar options (perhaps lines on top of the pergola).
6. More deck. We already had about 900-1000 feet of deck but it was awkwardly configured and not very usable. We're adding about 400 feet more deck, and have already begun mapping out how we will use it. We walked through it with the mindset "Pretend you are on vacation and are spending the whole day at the pool. Where could we have alfresco breakfast, lunch, dinner? How about hanging out and reading a book by the water? Where is the sun in the morning, noon and evening? What about family BBQs with a lot of people, where do we hang out, sit, eat? OK, what about a regular workday when we get home at 6 or 7, what then (since that's the majority of the time) and where can we lounge and unwind with a glass of wine?" My husband has mocked things up for me on the computer and I've even marked it out on the dirt with spare electrical conduit sleeves and pvc pipes, to see if it seems roomy enough for a picnic table or whatever.
If I were starting from scratch or had lottery money to redo my pool, a few things I'm not getting right now but wished I could:
1. auto-cover/simple shape pool that would accommodate an auto-cover (leaves/dirt/cleaning, water heat, safety considerations)
2. ledges/benches in the pool for lounging. We're more of social pool users, not athletic pool users, so we don't really need the space for a lap pool or volleyball but somewhere to set a frosty beverage is great!
3. Some kind of noisy water feature to drown out the sounds of my neighbor's pool/dogs/traffic (We plan to add a free-standing fountain some day. It's not really efficient for us to run our pool pump for this type of thing, since we don't need it to run that often to keep the water clear).
4. Automation of chemical dosing. We want to add a chlorine injection pump someday - our PB (and several others we interviewed) are anti-salt and we are happy with our BBB method, but with a large pool we lug a lot of bleach that needs to be added daily.
Good luck, can't wait to see your build!