I'm lucky in that I very rarely get anything nicked.
I tend to buy mid range hand tools and higher quality power tools.
Fancy toolbags and boxes look pretty but wont pay for themselves
2 sets of drivers 1 high quality insulated and 1 cheaper day to day set.
Cheap tools are ok if you are near to somewhere you can get replacements from.
In my case I can be 40 plus miles from anywhere and even then I'd get humped on price.
Sometimes my expensive kit sits about doing nothing for weeks at a time, but when needed it's worth it's weight in gold.
I would say buy things as you need them and buy the best you can comfortably afford at the time.
Power tools decide on a brand and stick to it that saves on individual batteries and chargers.
Personally I avoid cheap critical tools like the plague. If you factor in time lost and replacement costs when they break, they are suddenly not so cheap.