For TSA workers and/or frequent flyers, is it best to just have all your electronic devices in your carry on?

Sorry this might be a long read for some, but I need some opinions.

So basically Ill be flying this July 4th (have not traveled in over a decade and in my early 20's traveling alone).

Is it generally safe travelling with a laptop and dslr camera? Will it be a hassle going through security because Ive read they sometimes make you turn on your computer to inspect it further.

Also Im thinking of traveling with a Northface Backpack that will include my laptop, laptop charger & external harddrive. I will also have a duffle bag that will include my dslr camera (which is inside its own camera bag) along with batteries, chargers and some clothing. Is that too much electronics to carry on, should I think about putting some in my checked luggage?

Ive also read that some airports only allow 1 carry on? What should I do? Will I have to pay extra? Note: Im travelling out of Seatac airport in Seattle enroute to Philippines via SouthKorea.