Whilst this may be too critical, I find that if you wish to use Anki for proper "learning" rather than simple memorisation, cloze deletions are the wrong way to go about it.
They suffer from being too easy to get wrong and too hard to get right, as well as your brain often just recognising the pattern of the words in the text rather than the information itself.
If you want to make good cards in general, you need to think more in terms of building up a detailed corpus. Interlink cards, establish key concepts in a field, focus on relations between atomic units rather than individual atomic or non-atomic units. In addition, include images to serve as useful stimulation for the visual cortex. The only real advantage I can see to clozes is a marginal speed increase.
