The size of your deck depends upon the type of learning content it wraps in itself, it will affect your learners experience if it is too heavy in size. Keep the following pointers in mind to keep your deck size moderate.
Have moderate number of images in your deck say about 20% to 30%
Make sure that the images are optimized with lossless image compression tools
If your deck also includes PDF slides, make sure that the PDF is also losslessly compressed
You can not remove all slides from your deck, there is a constraint to this. You need to have at least one slide in a deck. So keep deleting the slides till you reach a condition when there remains only one slide in the deck, delete button will be disabled.
This way you can remove slides from you deck with constraint of having at least one slide in it.
Deck Analysis is an essential tool that enables you to analyze the Quality of your Interactive Learning Deck using predefined rules that follows Micro Learning Principles. It will analyze your deck and give you suggestions on the same. It will give suggestions on viable Number of Slides that should be in a deck. How much interactivity should be present in a deck? How much visual content should be there in a deck and so on?