Minimalist doesn't mean no colour....
Also feel you've got too much 'line division' on the second image, it's too heavy when you compare it to the third image.
Think about what you'd expect in a planner, personally I'd be expecting public holidays, maybe even a page where you can add in important contacts (in case you lose your phone etc) and a London underground map. Yes I know a lot of those things can be on your phone but technically a planner can be on your phone too. If this is being given out to clients as a gift, then maybe a local area map of where you're based if they come to you, that sort of thing.Also, in your opinion what pages can I still add on my planner?
Think about what you'd expect in a planner, personally I'd be expecting public holidays, maybe even a page where you can add in important contacts (in case you lose your phone etc) and a London underground map. Yes I know a lot of those things can be on your phone but technically a planner can be on your phone too. If this is being given out to clients as a gift, then maybe a local area map of where you're based if they come to you, that sort of thing.
In essence, think about what you'd like to see in a planner, then see if it's something that isn't too difficult to add.
Good article here - https://indesignsecrets.com/designing-calendars.php
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