First, the obvious
Some things are going to be on the wishlist for any "next version" of a mobile device. Sharper display, longer battery life, lighter and thinner build, faster performance … these things apply to the Surface Pro 4 just as they would the Galaxy S7, iPhone 7, iPad Air 3 or HTC One M10.
... in other words, "duh."
The Surface Pro 3 is already in pretty good shape in all of those categories, but its display resolution could afford to be sharper for tablet mode (when you hold it closer to your eyes). It looks outstanding at laptop distance, but at tablet distance, we do notice pixels. Upping its resolution could kick tablet mode up to the "dazzling" eye candy level that the SP3 falls a bit short of.
A lighter build would also be a big improvement. The 12-inch SP3 makes for such a huge tablet that a feathery build would help to make up for the fact that you're hoisting a device with a screen that's 47 percent bigger than the iPad Air 2's.
Give the Surface Pen a (better) home
The Surface Pen in the Pro 3 is awesome. It has a solid aluminum build, great sensitivity and can even launch OneNote with a one-click shortcut.
But Microsoft hasn't been quite as successful in handling the Surface Pen storage situation. Sure, you can slide it into the loop that attaches to the keyboard, but that takes some finagling – and isn't something you'll want to do more than a couple times in one session.
You can also snap it magnetically onto the right side of the tablet (well, it's the right side in laptop mode), but that's also where the Surface's charging port is. If you're charging while you're working, and you don't feel like messing with the keyboard loop, you have nowhere to put it.
Why not just magnetize the device's left side as well? Then you can snap the pen on even while charging, for easy access and easy stashing when you're done.
Silence is golden
On our Surface Pro 3, the fan fires up often. And loudly. Either a fanless Surface or one with a quieter fan would help to push things forward.
One option would be a Broadwell Core M processor, like in Apple's 12-inch MacBook, but that would also mean a step backwards in performance. So perhaps a quieter fan that can do its job on a newer model Core i5 or i7 without setting off tornado sirens would be just what the doctor ordered.
The Surface Pro 3's keyboard has a much better trackpad than on any of its predecessors, but there's still room for improvement. Try switching from a MacBook to the SP3, and you'll see what we mean – you'll be going from a huge glass pad that's incredibly responsive to a smaller plastic one that's ... sufficiently responsive.
There's only so much real estate to work with on the Surface keyboard cover, but if Microsoft could manage a pad that's about 25 percent bigger, with improved sensitivity and perhaps a higher-end material (glass?), that would be a big win for the Surface Pro 4.
Bring back the Power Cover – and make it standard
We're already asking for a lighter Surface Pro 4 with a sharper display, and doing both of those and extending battery life would be a very tall order. So why not put some extra battery in the keyboard – like Microsoft did a couple years ago?
Microsoft never released a Power Cover for the Surface Pro 3, presumably because the device's battery life was already pretty darn good. But you can never have battery life that's too long, so why not resurrect the Power Cover for the Surface Pro 4? And why not make it the default keyboard cover?
Cost could be an issue, and a US$200-ish price tag for the keyboard alone (after throwing down nearly $1,000 for the Surface itself) would likely kill this approach. But $130 for the non-battery Surface covers always seemed a bit steep to us, so perhaps a $160 cover with a built-in battery could be a reasonable compromise for both Microsoft and Surface buyers?
One more USB port
We don't have a big problem getting by with the Surface Pro 3's single USB port, and you can always add a Surface Docking Station (or a cheap USB splitter adapter) if you want to expand that. But one more USB port would still be welcome.
There's also the question of whether to switch to USB Type C, or stick with the current model's USB 3.0. We could live with either approach, but our only request is that, should Microsoft go the Type C route, include an adapter in the box.
Free Windows for life!
We're probably venturing into fantasy land here, but when you buy a Surface, you aren't just investing in Microsoft's software platform, you're also investing in its specific vision for the future of the PC. Why not thank the buyers that are helping to make that a reality by promising free Windows updates for the life of the product? Meaning Windows 11, 12 or whatever comes next will be free upgrades for that Surface, as long as the device's specs fall above the minimum for that Windows version.
We won't hold our breath for this one though. It could be too big an incentive to buy a Surface over a similar device from HP, Lenovo or other Windows OEMs, causing unnecessary friction with Microsoft's partners. Oh well, it can't hurt to ask.
Surface Pro 3 owners: what else would you want to see in the next version of your favorite 2-in-1? Drop us a line in the comments below.