The lack of crispness you notice in many games and not in others is due to whether the given app is running its own internal resolution upscaling. To compensate for games that dont automatically upscale you will need to run the oculus debug tool and increase pixel density override to 1.5 or more and your fuzziness will be gone.
For the fogging of the lens, you need to let the rift heat up before using it. I'm in the UK too and my rift lens are quite cold before I put it on my face and my body heat will cause the fog. If you open Oculus Home for a bit before you jump into the rift it will heat up the device and I won't get any fog. If I do it only lasts for a few mins while the lens are still warming up to my temp and then it will disappear for the rest of the session.
Once you've been wearing it for >30min do you still get fog? After this amount of time the lens should be the same temp as your body and not fog up.
If you are still having problems I'd suggest getting a USB fan and point it at your face. Plus a nice bonus, it can also help increase presence if you are also outside in a VR game, as its like simulated wind 🙂
i dont get fog,but the topside of the rift warms up.. and i can feel that on my fore head.. i dont know if its normal.. but it is not a big plus for me 😉