To me it seems, that most problems stem from the Android 10 upgrade.
That raises hopes of course, that the troubles can be solved with a bug fix / update, they are already working on.
See the post on support status by rae, that confirms increased support requests with Android 10 / FP3+.
Hardwarewise the FP3/3+ is way more sturdy. It is bending and twisting less when worn in pockets etc, Therefore the contact problems and troubles with the modules are much less likely to occur on the FP3/3+.
Most visible is this regarding the display.
With the FP2 it was just clicked in with 2 plastic locks, while it is fixed with 13 screws on the FP3/3+.
And mine works without troubles as well; it’s running on /e/.