For years, I just had a 'medium' digital camera, which turned out to be absolutely ideal for certain situations, when I got a 'proper' DSLR, it was definitely less useful in exhibition situations, particularly.
So I currently run a full-size DSLR ( which accounts for 80% of the pictures ), a "packet of twenty fags" pocketable camera and now, also, a smart phone, which I only use as a "small bar of chocolate" camera for certain situations.
I do keep the 'middle' camera in the car - for when somebody hits it...
It's all about what you want to do and what you can spend.
I have recently reorganised my pictures into better defined subject areas in the 'main' computer, but have left them in time order in the 'laptop', so that I have a bit of a back-up and two ways of trying to find a particular one.
I do a separate back-up every few months - and leave that on another premises.