The DAB decode just takes some time - DAB will always have more latency than FM due to the increased processing. Not sure how much that can be shrunk (probably a fair bit but the cost wouldn't be worth it for most people), but the crossfade would not work because the FM would be ahead of the DAB.
The only way to avoid channel changing delay is to constantly be decoding multiple channels, which would likely increase the power consumption and device cost a fair bit.
Masturbation won't do that, you should probably go to a doctor. Also, give a toy a go if it sounds fun!
Fluorescent lighting 100%. Warm dimming LEDs behind a nice shade, on the other hand, can stay (preferably dimmed).
I tried PCAPdroid recently and that seemed good
As someone who just switched to an Xperia as it's one of the few phones that still has a headphone jack, NFC, and microSD slot, this sucks. The software support is the biggest problem IMO because the rest is great.
Look into Gadgetbridge, as that allows the bypass of proprietary apps for some trackers
PB&Jegg
I loved Lego Island but will never forgive Lego Island 2 for the bad disk that would crash after 3/4 of the game. I never got to finish it.
Rock Raiders & Lego Loco were great (if a little inadvisable in terms of the Lego Loco letters).
This comment from A7pr8 seems to suggest it is possible to modify the apk via Lucky Patcher, which hopefully would then work on a non-rooted phone:
You can't just send the app from your rooted device. When you mod the app on a rooted device only .odex file will be patched not the .apk file.
You need to rebuild .apk to be able to share it and the the other device should also has luckypatcher for it to work.
Simply when you patch an app use the option create modified .apk or rebuild it from "rebuild & install" in the bottom bar.
Simple File Manager (and the other associated apps) got bought by a company, so this is a fork by a long-time maintainer that keeps it FOSS
BIFL and Bluetooth are typically an impossible combo because Bluetooth means more batteries and electronics to break/be unreplaceable. Maybe modular systems will come in the future but they'd need to use a completely generic set of batteries.
My best suggestion, based on what you describe as your problem with wired headphones, is to get headphones with a removable cable, as those cables are generally pretty standard. I know sennheiser had a lock in mechanism but you can get third party cables. Also, I was able to take that out of my HD599s and use the headphones with a Bose cable.
The fade-out could work but would add more delay time, but the buffering would almost certainly require additional hardware because radios typically can't process two DAB signals at once and it can't pre-buffer a live broadcast unless it adds an extra delay, which is just shifting the problem to a different cause. Speed ramping could maybe account a bit for this, but then if you change stations multiple times quickly this would fail. Also, speed ramping would probably annoy people, especially for music, unless imperceptibly slow. That would require a decent buffer, meaning you'd have to delay switching the channel and also not change the channel for a bit, otherwise you'd get the pause.
The amount of complexity any potential solution adds is not especially worth it, as much as I recognise that it is annoying. Also, since most people aren't too fussed by the pause, I doubt anyone would bother to produce a radio with the hardware for this (and the software on top).