I really like my current setup. I have an iPad 11" Pro with the pencil and a small keyboard (Logi MiniMX). I picked up a small adjustable stand on Amazon for the iPad. Setup has a small footprint at the table. I use three apps; Obsidian for all my typed reference stuff and to take quick notes; GoodNotes with a character sheet pdf that I write on with the pencil; a browser open with Pathfinder Nexus (I own all the rulebooks there) but this could also be the Paizo pdfs in a different app. Pathfinder Nexus is easier to search quickly. iOS has a really nifty, free program for collecting pdf’s called BookFolder. Once the character management on Pathfinder Nexus is fully operational (open beta for now), I may ditch the pdf character sheet for that.
There are several apps that let you upload a pdf and write on it in iOS, but GoodNotes is very popular and works beautifully! I also have a screen protector that makes the screen feel a bit more like paper.