I know navigating the Desktop Mode without a KB Mouse can be quite frustrating at times, even with the trackpad. You can use your phone as a wireless BT keyboard and mouse connected to the Steam Deck, and navigate the Desktop Mode with ease. I have tested this on my Galaxy S23U (Android) and it works perfectly! This is also convenient if you are outside and want to do some stuffs in Desktop Mode, without having to carry any extra devices.
Google Play Store Link:
https://play.google.com/store/apps/details?id=io.appground.blek
Install the app, run it and connect to the Steam Deck via Bluetooth.
I feel it is a lot easier on the mouse control using the phone screen than the tiny track pad. easier to drag and drop, left right click etc. slight upgrade at the least lol
IMO the single best change you can make is to move Primary Click to the Left Trigger or other button on the opposite hand. This frees your thumb to focus on precision, or take full advantage of trackball mode and flick the cursor across the screen.
The people who insist the default is Right Trigger = Left Click because it’s “like using a mouse” are, frankly, just wrong. With a mouse, you are using your arm/wrist, which doesn’t “compete” with your clicking finger like using your thumb does when using the thumbpad.
The only reason “Right Trigger = Left Click” is default is because that’s what people are used to with conventional dual-stick controllers, but it’s absolutely sub-optimal for trackpad control, especially with their lower positioning on the Deck.