Just note that with Bambu printers about past data collection practices and their in general mid to atrocious after-sales support. If this doesn’t deter you, then go ahead and get one.

I do a lot of my functional parts in ABS, ASA though printing such material may be difficult on an open-air machine. The two obvious choices will generally be PLA or PETG. PLA is one of the most common printed materials, and is fairly balanced in material strength. PETG parts are more likely to permanently deform heavily before fully snapping, as well as they have a but more temperature resistance than PLA. Additionally most PETG plastics hold up decently well to UV, often making them more suitable for parts that need to be outdoors.

PLA takes not much consideration on surface to print, as most printers come with a smooth PEI build sheet by default. It will however need more cooling than printing with PETG at equivalent speeds. If you use a PEI sheet for PETG, make sure it is textured. You will destroy a smooth sheet if it doesn’t have some kind of release coating to lower its adhesive properties to PETG.

There is no guarantee for spools of filament to actually arrive dry, so a filament dryer isn’t a bad idea. I don’t have any particular recommendations for a good filament dryer. I have a Filadryer S2 from Sunlu, but am not impressed by it.

We are well beyond the point of a majority of common hardware having built-in kernel drivers and userland software for extra stuff like RGB control that the best advice is rather avoiding Linux, to instead avoid the trash hardware (NVidia for the time being, GoXLR, Broadcom, etc.). My GPU, audio hardware, network interfaces are both popular products and have worked out of the box for years now.

The heated bed is coupled to a thermistor. I’d argue controlling the temperature in order to not accidentally overheat parts of the phone is a step above a hair dryer.

The desired alternative is not Matrix simply because privacy-conscious, open-source ecosystem vs. proprietary solution is not the goal. Matrix would still generally be terrible for support. What people want is publicly searchable content that is ideally indexed like a wiki. Many will happily settle for issue boards or even forums though. Discord has pathetic search capabilities in comparison to any search engine and has no way to properly and publicly backup information that is posted to the platform. With a website of any kind, one could clone the site for mirroring or simply get a web archive service to crawl relevant sections.

There are not many Android phones that actually let you flex the open source benefits of AOSP. Android as it is packaged on many devices is not open source, and nor are the devices willing to fully let you install what you want. Ironically some of the only choices you have with the highest degree of freedom are from google.