Here's my 2p-worth
is a 110D / 120D out soon
I doubt it, but when it does arrive its unlikely that anyone Joe Public will know beforehand. A "revamp" is more likely.
I recommend that your buying decision is based more on the Range you need. If you can make all your regular journeys on a 75 then no need for the 100. You could try using
A Better route Planner to try some journeys that would take you "out of range" (it lets you choose Model / Heavy-footed-ness! / weather / etc. and then routes via Superchargers and thus you can compare Journey Time / Time-to-charge / stc.)
All model charge 10%-70% in the same time (above 80% the charge rate slows down dramatically), so with 100 you a) go further before having to charge and b) get more added-range more quickly
if they did release a faster version down the road
I have P90D (Insane, not Ludicrous). As I understand the difference Insane boost is effective 0-30MPH whereas Ludicrous maintains the boost 0-60 (and maybe beyond). So perhaps better for passing too.
I'd prefer the P100D but I don't think it's worth an extra £300 a month
I gave loads of launch-rides to mates when I first had it, now I rarely use P-mode at all. 90% (or more) of my driving is either motorway or town / bumper-to-bumper, a small percentage is country roads and being able to hustle is fun ... but rare.
I'm ancient, but when I was a kid the Car Poster I had on the wall was 0-60 in 5 seconds, and I thought that was the definition of mega-fast. Tesla doesn't make anything that slow
If I am driving, e.g. wifee as passenger, and car is NOT in Insane, and, say, there is a short gap to get onto a roundabout she hates it if I hope onto the roundabout [because I can], Unless she happens to be concentrating, in the way a driver would, it comes unexpectedly and makes her jump ... and if you don't have everything in the cockpit nailed down a Launch will sling it all into the boot

With P-mode it would be uncomfortable or her, rather than just alarming ...
Of course, using Man-Maths etc. etc. the next one I have might well be P-model too ... but ...
Not entirely sure, but I think P-Model on Range-Mode may eek out a bit more range (it can favour using one or other motor on its own optimise for cruising speed), but generally P-Model is regarded as having (fractionally) less range than S-Model
Much will depend on your driving habits. Mine does 27K miles per year, daily commute is 80 miles (so that in itself is a fair bit), and Supercharging (out of range) is a once or twice a month thing.
I get 220 real-world-miles on a warm day. I keep 20 miles "reserve" and I always charge to 100% if my journey is more than 160 miles (in case of detour / errand-request / foul weather).
The ABRP ranges I have come up with in the past are:
MS75D 324 Wh/mile, Range 203 (best to deduct e.g. 20 miles "buffer")
MS100D 324 Wh/mile, Range 274
MS P100D 340 Wh/mile, Range 260
For my MS P90D ABRP gives 340 Wh/mile, Range 217 - which is close-enough to my own experience of 220 miles, so hopefully the others are representative.
the 21" wheels will likely rob 20% range (compared to 19" wheels)
You'll be inundated with offers of referral code. Pick someone helpful, or a local mate. If you want to use mine you can have whatever swag comes with it - provided you come and pick it up!