Well, your laptop:
they will ask that you not run in the air it if you can't disable wifi. They may do things to discourage you from using your laptop, such as seating you in economy class.
Your cellphone: on landing you may hear a bunch of "Welcome to roaming greeting messages" (in europe with international travel, it's quite common) on landing. That's the shutting off of the "airplane mode" of cellphones that are left on in flight. Many phones don't have airplane mode or it's disabled. Still, turn yours off.
I don't remove my shoes anymore, but I do stuff all my metal stuff (except my watch, but it has a leather band) into my coat, and slide that through. They will ask that you remove the laptop from its case. The laptop is the last thing I send through the conveyor. 1 in 14 laptops sold gets stolen, and a classic trick used to be to grab them on the other end when the schmuck was tied up iwth security: everybody's watching what goes in and through the checkpoint; few watch what happens afterwards.
Pressure: I've started taking water to fight dehydration. Take a full, sealed container to altitude before opening it. If you don't finish it, and drink some during a layover, deform the bottle by squeezing it. It'll pop back up in flight.
Upgrades: you ain't getting one. The following tricks have worked for me or close relatives:
A) Flying a bunch on full-fare econotix with a frequent flyer card.
B) Buying coffee for a flight attendant stuck 10 people behind you in line (oh gee, I didn't know YOU were on my flight...
C) Having someone abusive challenge your for your seat.
D) Having gate agents point to you and complain about an abusive group of pax (this happened to me.)