I don't seem to have that problem in CS6. I select/drag the topmost object no matter where I click on it. Can't really speak for whether it changed in CC.
AFAIK, you can't change any aspects of the default behavior that would help ease your problem, but there are some habits you can develop to make selection easier:
1. Use layers. With some basic planning, The ability to lock or hide non-target layers can make managing your views, as well as selecting and manipulating objects much easier.
2. Pay close attention to the cursor. It changes when in position to select an object or move a selected object.
3. Use the arrow keys to move an object rather than click/drag.
Thanks for your answer, you do confirm one point, I didn't think this was happening when I was on CS6, I just couldn't be sure. It looks like Adobe have either missed this fact in CC or even worse, supposedly upgraded it to a better feature, when in reality it is just a nightmare!
Although your suggestions aren't very useful, thanks anyway, see below.
Layers: I do use layers all the time, but that won't prevent the deselecting of the object.
Cursor. I bet you don't need to pay micro-attention to the cursor when just moving an already selected object, extra stress is what it is!
Arrow Keys. Not very practical, especially when I already have hold of the mouse, plus I lose my smart-guides.
The solution is for the engineers to fix it, I think I may need to get more proactive with my feedback.