Developers are not always on the ball when it comes to fully supporting any OS, tablet or desktop. That is frustrating when encountered. I think tablet app developers are even worse than desktop/laptop developers though.

As far as features, iOS still has a long way to go IMO. Apple still puts too much emphasis on looks and not enough on function. They need to forget the looks for now and concentrate on function. It is a touchscreen OS designed to be used primarily through finger input. Some people use a stylus, some add a keyboard, some other input devices, but it has to be designed to fully function by finger input alone, otherwise it isn't a tablet OS. But they should also build into it the functionality to work with mice, pens, keyboards, etc. They have some of that integration ability now, but it needs a lot of improvement.

I really don't think we will ever see a company like Apple turn a tablet into a laptop/desktop replacement. That would not make sense from a business perspective, and stockholders would be upset. They will try to keep it a highly desired additional device that consumers feel they really want and need. Quite frankly, I want my iPad to be a tablet, not a laptop replacement. I prefer portability with a sufficient amount of power and functionality to more than adequately accomplish away from home tasks for which an iPad was designed. Turning it into a do all machine will likely make it lackluster in much of its functionality. Leaving it highly good at the tasks for which it is designed makes much more sense to me, and makes it much more useful to me. One major thing that I do wish is that they would implement a better file system. I want to be able to connect my iPhone/iPads directly to my Macs without having any interface like iTunes (a suckfest) or iCloud and be able to drag and drop files between them. Having this ability with Windows PCs would be great too. Currently it is a PITA to transfer files, and it shouldn't be.

ETA: One simple change could drastically improve the finger input. Use a darn keyboard with numbers and letters and a few of the most common special characters on the same screen! It takes forever toggling back and forth to enter passwords with letters, numbers, and special characters. I realize the iPhone screen is limited in space, but there is plenty room on the iPad screen. And yes I know there are 3rd party keyboard apps but they don't integrate as well as they should, and none I've tried are very good. I hate having to toggle or long press, and we shouldn't have too.