I had similar qualms before I got my 75D. With Tesla there's always an minor or even a major update down the pike and it's impossible to time your order "just right" I had 90D confirmed 2 days before they announced 70D will be 75D instead with only a 20 mile range difference. Paid the $500 change fee to bump down to 75D and not regretting it. Personally, I think the software locked 60D option is an amazing value and I would have gotten that instead, if it was available. I now think of my 75 as an unlocked 60
Bottom line, the car is next level stuff. You will enjoy it, don't worry about what's coming later. Waiting for AP2, AP3, new/updated this and that only means you are not driving the dream that much longer.
Plus you can always trade in/upgrade in a couple of years when AP4.5 is out if it matters that much to you
Pull the trigger and enjoy! And if you haven't used a referral on your order to get $1000 off - I here's my code, your DS should be able to add it even after the Order confirms: Referral | Tesla
Either way I will be sure to use your code.. Was waiting to add that till I decide for sure and not block someones tally