Here is my current cart - anything I am missing? Imgur: The magic of the Internet
That being said, I currently plan on buying the X1C/AMS combo.
Any discount codes / coupons to be had?
What about other accessories? Should I get a 0.8 nozzle for functional stuff? For swapping, do I buy the Complete Hotend assembly or just the hotend?
Is anyone using an E3D hotend with theirs? I have several tungsten nozzles I would like to use if possible…
No coupons that I am aware of.
Yes, get a spare 0.6 nozzle assembly for sure. If you think you’ll be printing really big stuff then grab a 0.8 too. I would just get the complete assembly, it makes it super easy to swap between nozzle sizes without having to mess with any thermal paste.
I cannot comment as I have not done this.
I wouldn’t bother with 0.8 nozzle. You’ll be disappointed.
Even 0.6 is not really needed, except when your filament calls for it due to larger particulates/fibers in it. It is going to print faster, but not by much. The printer is moving so fast that you’re going to hit the flow rate limit even with 0.4mm nozzle and while 0.6mm nozzle enables you to extrude more filament, it doesn’t mean that filament is going to be properly melted. Just get a 0.6mm and move up if you feel you want to.
I also wouldn’t bother with the Silicone socks. I have only damaged one so far, because I was cleaning the nozzle with a blade and cut into it… but that’s the one I currently have on my printer and it doesn’t really matter 
Every replacement nozzle also comes with a sock so you’ll have plenty of spares.
I would get a replacement 0.4mm nozzle and I always buy the complete assembly (so now I have a bunch of spare thermistors and fans in my worn out nozzle assemblies:)). I have never had either of those fail, but I also don’t like messing with thermal paste and wires. If you need to swap it, you’ll want to have the complete assembly in hand anyway. I might switch to just the hotend one day and just prepare a few spare assemblies. You also don’t need to change the nozzle that often (unless you’re printing lots of CF or glow-in-dark). Your call if you want to pay for convenience.
Regarding what could be missing, that depends on whether you already have some accessories (you already have another 3D printer). You should get some adhesives (glue stick works but liquid glue is better except when you need to create a barrier for easier detachment of prints), 3D LAC is good, I use it on the Textured PEI plate (but you can print most PLA and PETG filaments without it). I’d get 3D LAC somewhere and buy a glue stick from Bambu, that should cover mostly everything (I assume you’re not going to print Polypropylene much :))
You’ll also want snips, small ones. And some sort of thin modelling blade (carpet cutter works fine, mostly). And boxes for filament, and a filament drier… Let us know how prepared you are
Anyway, I’d add another Textured PEI plate (possibly the new gold one, it’s supposed to be more resistant to abuse?), sometimes you want to let it soak in water to detach a print, and you’ll want to be able to print in the meantime and it will wear one day anyway.
I actually bought a bunch of spare accessories that I have never used, like belts, cables (because they are cheap but hard to get in a pinch), it’s up to you if you want to stash those.
I would also add the following if you have spare cash
I had the exact same questions as OP. I print mostly functional parts, lots of XX-CF. The 0.6 nozzle is required for some, but I do avoid it now due to loss of quality. But what I learned is that nozzle change is a PITA. If you expect to swap between two nozzle sizes you have to have two full assemblies. I got an extra extruder 'cause it’s supposedly a consumable, i.e. will break. I guess I’m echoing @zviratko
The must-have IMHO is the gold PEI plate. I used the hot plate once before I got the PEI and that was that. Someday I may want a smooth underside but until that day it’s PEI all the way! That thing is just awesome and the texture is very nice. (I wasted money on getting a spare engineering plate and extra stickers.) Also get the liquid glue, everyone likes it incl me.
I bought extra metal scrapers and have not used the metal scraper once. I printed the alternative little scraper and that or fingernails is all I’ve used. Or soak the plate in some soap to dissolve the glue to make little left over bits of brim release. Using a metal scraper on the textured plate doesn’t sound smart to me, but maybe it’s just fine.
For PTFE I would buy the 1m (2m?) length and not the precut pieces (which is what I did and regret). The reason is that this way you can cut different lengths if you want to place the AMS elsewhere or if you want to feed from a filament drier, etc. It just gives you more options. Yes, the day you need to replace a std piece you’ll have to snip…
For single colour prints I agree that a 0.6 isn’t a great advantage over a 0.4, however for multi colour prints the larger layer heights you can get with a 0.6 to 0.8 nozzle means a big reduction in the number of colour swaps and therefore a big reduction in overall print times.
I agree about getting the complete kit - as having to move fans, heaters and sensor is a bit of a pain. I also found that the screws to hold the fan on don’t seem to be available separately.
Nozzle swapping is a bit more fiddly on an X1C than it is on a P1P/S
The carbon filled fillaments are amazing. I would get atleast a roll of cf pla. Prints great with even the .4 nozzle. Also, using the engineering or textured plate, ive never needed a scraper. +1 on getting the complete nozzle assembly. Saves a huge hassle